Around 2015, I went from many years of playing 330g+ unstrung weight (Six.One 95) to 315g (Prestige Pro and others) to 295g (Graphene Radical MP). I've been playing lighter frames ever since. I've tried to go heavy again many times, but it just never works out.
The bottom line is that I love the control I get from lighter frames. That goes against most of what you read around here, but I find heavier frames to have inherent power from the weight that is harder to control (once you get it moving, it is harder to adjust or control). With light frames, I can adjust power and spin more easily with my swing speed, and even tweak things mid swing if I need to. And then the other obvious benefits are better defense, more spin on serves, and quicker reactions at the net.
I obviously lose the plow that you get with heavier frames, but I'm willing to give that up for all of the other benefits. Even at the 4.5 level, it is very rare (but does happen) that I come across somebody that hits big enough to make me wish I had something heavier.