not sure why 3.0 would cause any issue and 2.4 would not – if anything 3.0 should perform better.
I had a look at your Tools > Site Health >> Info >>> Server.
I don’t have much experience with a Litespeed server but some of those settings seem a little on the low side – in comparison my default setup is generally this:
PHP max input variables 4000
PHP time limit 1200
PHP memory limit 256M ( front end and admin )
Max input time 600