All build servers are like this. When you move in GMod, it’s just like in TF2, and it was announced to be like this in an update some time ago. Not in SP though, SP still has very clean-cut movements.
It’s not a laggy-style slide, it’s just that you don’t stop when you stop moving, you slowly come to a halt after about another step and a half. This isn’t appropriate in GMod, I don’t want to have to be in noclip to do anything correctly.
If you are so adamant movement hasn’t changed, I don’t feel like debating this, I really just don’t care. SP has different movement to MP, so let’s say I would rather have SP’s walking style to MP’s. I am sure this could be pulled off.