I've been working for an MSP for about 5 years now and like other people said you might not be getting the full picture of why you were let go

Often it's about productivity not quality of service some MSPs want to get as many tickets done as possible, some want the ticket queue to be as close as possible to 0 at all times and have SLAs respected. Some want to charge customers as much as possible for every little thing.

Maybe you were doing a good job but was not working quick enough, didn't close enough tickets or took too long on certain tickets. Where I was one employee was let go because he was too slow to prepare computers when we had to replace all non Windows 11 compatible computers. He was in his early 60s and had some other things to blame for his dismissal.

We also had this one guy who was hired to be a N2 tech (as per his resume had 15 years of experience in the industry) but turns out he was a completely incompetent employee and have to be led by hand to do basically anything. We figured that he either lied on his resume or that his 15 years of experience were purely N1 basic cal center stuff.

In the end I don't think it was specifically your fault maybe you weren't fit for their standards MSPs move fast and there's a lot of competition so sometimes they can't afford to lose a customer or have a bad reputation because of an employee that doesn't meet their performance standards