I was a Snap customer for a couple of years (I think) before they were bought out by 2 Degrees, and I certainly noticed a significant change in call centre wait times, and the helpfulness and knowledge of the staff after the takeover.
TBH, I don't think I've dealt with a more friendly and helpful call centre than Snap's - calls usually answered within seconds , personable and chatty staff who would work to sort out a problem until it was fixed. Post 2-degrees takeover it became more like ringing any other ISP I've been with - a frustrating experience best to be avoided if at all possible.
That said, at least I could talk to someone - I'm not yet sold on the requirement to sort out any issues with my ISP (BP) via email, but that's something I knew before signing up, and luckily the service has been reliable thus far.