1. You can still play ATSMP, though only the Europe server is actually online.
2. I don't know if this is what you mean, but I will mention it anyways: No, you can't get your money back as you paid for the game (American Truck Simulator). TruckersMP is a mod, and is in no way affiliated with the game nor it's developers. TruckersMP only acts as a link between players for them to see and drive with eachother.
3. TruckersMP does accept donations, and from what I know they really help. Aside from this, the mod also gets money form ads run on the site. If you want to, you are more than welcome to send in a donation. I'm sure it would be greatly appreciated.
4. Making TruckersMP a paid mod is legally impossible, at least the last time I checked. This is because TruckersMP is just a mod, purely run by standalone developers. Making a paid product that's totally standalone from the actual game developers is illegal as TruckersMP and it's developers don't own the trademarks to the base games, ATS and ETS2. If the leaders of TruckersMP actually decided to take money from people to let them play, then I am 99,9% certain the owners of the game would take them to court pretty f'n fast.
5. Even if TruckersMP had the money to run the US1, SA1 and AS1 on separate, high-end servers then the debate is, why? When these security patches are rolled out to the servers, it's safe again. There's literally no reason to actually running them on such a system as that probably wouldn't lead to any actual player benefits. The only thing this would probably lead to is a complete waste of money. Those servers have probably been run like this for a really long time and in my eyes this hasn't had any negative effect on it's players up until now. The issue will be solved and everything will be as great as it was previously. The positives of this solution of running shared servers compared to the more expensive one though is that the most popular servers instead have gotten really beefy systems being able to keep up with the extreme loads.
Someone reacting to a post is nothing weird and is a part of this forum, as it is with many others.