We get it – you’re pushing VPS.
Having a 4 CPU limit on a shared service on a server is not really much if any different from having a VPS with access to 4 CPU cores …. on a server …. with other VPS. Is it possible that usage by others on the node would cause issues in both cases? Yes, 100% possible.
Would it be possible for them to exhaust all of their CPU on a VPS and have ‘faults’ [things slowing down]? Yes, 100%. But in that case it’s not just the PHP that would be throttled but every process on the VPS – MySQL, the web server, etc.
There are definitely situations where a VPS makes sense but this is not one of them.
But as I said – we get it – you think a VPS is the solution to everything and you think shared hosting is bad. We understand, please stop pushing VPS – you’ve already done so several times in this thread.