Up to version 7.3.x, PHP included libsqlite3. Version 7.3.x offers SQLite 3.28.0
As of version 7.4, libsqlite3 is not boundled anymore and PHP uses system one. On Dreamhost shared servers it’s version 3.22.0 which is not compatible with many useful features added in latest versions.
So, unless Dreamhost finds a way to compile PHP 7.4 against a newer libsqlite3, we have a big problem.
We may compile ourself a custom version, but as PHP doesn’t allow to specify a path for that library, I suppose one has to try to override it with LD_LIBRARY_PATH… but then I’m not so used to Linux to solve this by myself.
Anyway, as of now if you use SQLite, beware about upgrading to PHP 7.4.