Yeah, it’s the same on my machine, I have never seen it lagging so bad. Just started a new 3d person project, it’s almost like there’s a memory leak somewhere? Just gets worse overtime. Not switching my main project from 5.3 until the performance improves. No problems with previous versions (mostly, been using 5.1 and 5.3).
Stats are :
Intel(R) Core™ i7-8700
RAM 32.0 GB
NVIDIA GeForce RTX 3060