Yeah I have the same problem too. I updated my internet speeds much higher than before and it helps with lowering ping and joining the server faster, but nothing with preventing the crashes. It's our computers that don't have the required specifications for running the server when the server hits a certain number of players, like I highly doubt you'd crash if there were about 10 people on.
With all these new add-ons and such the server has required better computer specifications, and if we want to play on it without crashing, we have to upgrade.
I have a meh laptop so I definitely need to upgrade haha.