Is beginner mistakes vs the alternatives [v5]

There is a lot of conflicting advice online and most of it is from 2019. Long-time lurker, first-time poster.

Mostly thinking out loud — feel free to push back hard. Been thinking about this for a while and curious what the community thinks.

Long-time lurker, first-time poster. Spent the last few weekends digging into this and the deeper I go the more questions I have. Not sure if this is the right place to ask, mods please remove if it is not.