I doubt that anyone cares, so consider this post a reference sheet I made after feeling rather tired seeing repeating inquiries about active multiplayer regions.

Since the game's multiplayer has definitely a evidence based confirmed regional lock, I hint towards my guide where you can reread how to change the multiplayer region by changing your Steam client's download region. I did it multiple times for this without any issues.
https://gtm.you1.cn/sharedfiles/filedetails/?id=2738776619

• Sunset in western Europe ~ around 18:00 o'clock GMT+1
  
• Saturday Evening
  
• 22k+ players online according to Steam statistics

Download Region Germany - Hamburg

English
https://ibb.co/wWd5F85
https://ibb.co/n0GDQC0

French
https://ibb.co/dK5K20P
https://ibb.co/Jp6Wy48

German
https://ibb.co/c23pQCf
https://ibb.co/mh78Xf6

Download Region U.S.A. - Maryland, District of Columbia

English
https://ibb.co/r6t9Sxx
https://ibb.co/gvXFWMC

Download Region U.S.A. - California, Los Angeles

English
https://ibb.co/4syVSBS
https://ibb.co/t27gt71

Download Region Japan - Tokyo

Japanese
https://ibb.co/jVQt6g4
https://ibb.co/476zF85

English
https://ibb.co/1qbp8BG
https://ibb.co/RvwVDj5

Download Region China mainland - Shanghai

Simplified Chinese
https://ibb.co/3RJ8kj4
https://ibb.co/RH2564z

Traditional Chinese
https://ibb.co/xzB39mG
https://ibb.co/jv6tQz4

Download Region Brasil - Brasilia

Brasilian Portuguese
https://ibb.co/SJKpN65
https://ibb.co/qYpbp53

You can discuss whether you consider the current playerbase worldwide at this very moment is active or not. There is clearly plenty of activity with open lobbies and welcoming people to play with. If you count all lobbies together, you get a fair number.

What people have troubles with, from my point of view, is a cultural and technical understanding of how the multiplayer works. It starts with the highly questionable, not understandable region lock to begin with, and continues with the freaking weirdo bug which gives defective results when searching for a fitting lobby.

Take as example my French search:
When looking for the same language, it makes sense that only lobbies are shown with the same language. But when changing to ANY language, why are all of sudden the lobbies with the same language are hidden? It is because it is defective - presumably.

My thinking tells me, it actually is not working how it is supposed to be, and instead pairs you with people with the same setting you have.

As in:
You have your game set to English and seach for ANY language, you get only other players which have set their game to ANY language as well. Excluding the player pool who eventually have the SAME language as you. And vice versa. Most visible it became by comparing Traditional Chinese with the Simplified Chinese.

Clan up. Guild up. Free Company, or whatever you call it nowadays. Lobbies are fine. Random joining hunts absolutely not so due to how the multiplayer is designed. It is a matter of taste etc. etc. pp. however, I like it more how it is than it was with Monster Hunter: World, so I recommend to you to adapt. And the best way to do so is making use of Hunter Connects, Steam groups or discord.

Make a shout with the Steam forums or any other Monster Hunter Forums or the big discord which is not officially supported.

Let people know

• Your Hunter Rank
  
• Your Region
  
• Languages you speak
  
• Whether you want to voice chat or not
  
• Time of the week and day when you are good to play with e.g. 7pm-9pm GMT
  
• What you are looking for and eventually some words about yourself

Basically: treat the game as you would play an MMORPG - in a MMORPG you get the best experience only with a group of players you can enjoy the game together. I think people call it nowadays "socialising" - it used to be "normal".

You can create a Steam group and invite the players who answer you forums thread which is titled something like

"Looking for players: 6pm - 9pm GMT, discord voice chat"

or invite them into your discord server - I read it is free to create one anytime.

Fill your Steam group, discord server or Hunter Connect with 20 players who are willing to play regularly together, no matter if daily, only weekends or whatsoever. And when a player becomes inactive in that group, do the same what clans/guilds do - redo the recruitment process to refill the ranks.

I cannot stress it out enough how much more enjoyable a Monster Hunter game becomes once you start to play with proper/fixed hunting parties instead of relying with weird expectations on random joiners. SOS flares were never good, as in: it was never my cup of tea. But if you insist on such: you will not get it in Monster Hunter Rise. Keep on suggesting what you had in Monster Hunter: World for the next installment if you want it that badly, but also respect those who prefer multiplayer like it is - it is more comfy with four hunters chatting together, laughing together, crafting together and playing often together - rather than hi&bye see you never again.

You have all the tools available to make it a very enjoyable multiplayer experience.
On PC it is so much more easier than on the Nintendo Switch, even!
Make use of the tools. Do not wait for something to happen when you can take care of that yourself. Especially when you have to.

Just the other day I joined a "Call for Help" thread in the forums. Go ahead. Post stuff like that. I would love a "Looking for Group Section". Too shy? Join my experimental thread then.

https://gtm.you1.cn/app/1446780/discussions/0/3278068270792070168/

This game is far from dead. If anything it needs just a proper awakening. No Monster Hunter game is ever dead unless the last of their multiplayer server is down. Why? Because you will always find players who love playing the game for the sake of playing the game. Spend less time being annoyed of this and that, and enjoy gaming to the fullest - it does not even have to be Monster Hunter Rise, you know.

*sigh*

I do not use discord. But I am pretty sure based on some annoying people I knew, anyone can create any number of free servers there. Same goes for Steam groups and you can make a fair number of Hunter Connects. The Monster Hunter community is made of very good people with a few less good exceptions. Cheer up, and let others know you are there. It is unlikely you will be ignored when you show you wish to play together for fun.

Really.

Happy Hunting ~