This reveals a fundamental problem in coding. Best practices for performant code shouldn't require ad hoc digging into PR's, and as long as it does then we'll have code that is buggy & slow(er than necessary).

Learning from others, in any field, will always be a valuable source of improvement, but it just doesn't seem that, in software dev, it results in laying down solid incremental increases in general knowledge that makes its way back into the education of future devs or current devs in a language new to them:

If this was structural engineering, you'd have to have taken a "materials" course and learn all about different types of materials, their properties, load capacities, degradation profiles and how to evaluate new ones that come your way under the same criteria.

Maybe that's what we need for software development. A structural engineer wouldn't use a composite material without knowing its performance characteristics. Why should a programmer use something like string collection from a language without knowing its performance characteristics?

This is on us to demand this, to standardize-- not languages themselves-- but the performance profiles & characteristics that we must know about in order to make a choice on which tool to use. And it shouldn't be that each user has to figure it out on their own, dig into PR's or whatever. Again, there will always be experiential learning. But too much is experiential right now.