Deleting Wifidiagnostics file and others under private/var/temp and /folder on Catalina
I would say no at this point, don’t mess with /private and instead open a support case if you catch the system not keeping it under 10 GB for a 250 GB disk. Other than swap files which can be controlled by choosing software that’s efficient or periodic restarts, the rest self clean quite well in my experience.

Unless you’re quite experienced, the risk/reward here has been high risk / low reward.

For instance, partial download and staged installers will be cached here, so if you find them and remove them, the system could have issues patching itself as it’s primed to install at restart after confirming a good download. Other things are placed here that speed up the mac greatly - so you just slow down the system as it has to recreate the files you just trashed.