We have a TS server. I have the app installed, but don't use it much. The link is at the bottom of the forum home page.
As Tom said, we have it, and have had for 11 years. Instructions for use are on the .net server at:
http://www.sim-outhouse.net/forum/showthread.php?t=40&p=389&viewfull=1#post389 A quick read of Dave's post should get you started.
Best to check if Bill (WND) is online as he can update your status (or leave him a PM). Teamspeak can also be used via the smartphone app, but voice quality used to suffer. Your mileage may vary.
The SOH server has many channels. Some are set up for specific groups (like the CFS2/3 'teams') but many are for some form of general use. BTW, quite a few of the developers that frequent SOH have used our TS server while working on models and it's a great collaborative tool that's underused.
I'm not on TS as much as I used to be, although I try to pop in most days. Either as a single person, or a group, if you want a tour drop me a PM and we can arrange a time that fits.
The next problem is finding people you want to talk to (and/or fly with). I always though we'd see an up-tick in users with tons of people at home, starving for contact during the pandemic but -nope! Working out subjects of interest, time-zones, learning new software, investing in a headset, using the internet interactively - there are a lot of things that have inhibited people over the years. If you look through the online-multiplayer forums -not just here but Avsim and FlightSim as well, you'll see years of posts trying to cajole simmers into the world of multiplayer with little gain. Of course, we never had the power of M$ to gently 'force' people into becoming connected while simming. MSFS is changing that.
The other issue is that people that DO fly online have tended to drift off to form small, limited groups of special interest, often wanting to maintain the exclusivity. That makes it hard for newcomers to find groups or get involved. That too may change.
Discord, or any of the other voice/video apps will do. Of course, many of those designed for the smartphone set also may be full of tracking and ads to pay for the flashier interface. Then again it also leads to more fragmentation of the community when you have so many alternative tools.