In the early 2000s, everyone in my bubble knew that PHP was a security nightmare, only seconded by Flash. In the meantime, Adobe gave up on Flash, but PHP is still alive and rocking.
How did that happen? Did PHP get some serious makeover? Do developers just not care?
It’s not more expensive. Shared hosting pick a fixed capacity and they try to cram as many customers as possible per shard. That includes shenanigans like putting two resource-intensive accounts on one shard and 50 low-resource accounts on another even though they’re all paying for the same tier.
Yes with Node you have a process per account but it’s easier and cleaner to manage resource limits like that. I will take managing shared Node hosting over PHP any day, it’s much easier and more secure.
Overall the cost of shared hosting with Node or PHP is the same, what you don’t do is offer both at once because it complicates things. Typically you let customers choose the backend language option (PHP, Python, Node) and a database engine (MySQL, Postgres, Mongo) and that’s it.