I mostly play bullet so I don't know how frequent is this, but in my experience the people here on chess.com are almost all very good-behaving. Yes, sometimes you get a cheater, but in my experience is not over 1%, probably less.
Long move timer

The issue is not relevant to bullet as games are over so quickly. But for 10 minute games - the most popular time control here- it can easily be relevant. Want to sit and wait 6+ minutes at move 3 ?? Having to wait 4 minutes is bad enough/ not all that uncommon as players are gaming the clock.
A line needs to be drawn somewhere. CC policy is 50% of the time control. Quite lenient.
I mean there are a lot of ways to don't let this make you wasting time. One method I use is to maximize volume and put the phone / pc down, I take a book and read some pages until I hear the sound of the other player moving
It happened to me sometimes that someone wasted time, but more at the end than that at the beginning
I think you!d be very surprised at the frequency of the abuse that would occur if allowed.