Per https://caniuse.com/?search=-webkit-transform, transform without a vendor prefix has been supported since Chrome 36 in 2014.
Personally I'd prefer to simply remove old vendor prefixed CSS definitions but that would first require a shared understanding which dates (and/or which browser versions) are "too old" for Phorge code.
See "List of changes, most recent first" on https://www.mediawiki.org/wiki/Compatibility#Browser_support_matrix for a random example.