[DTT]

>as I really don't think that smaller studios do

A great amount of indies do. Super Meat Boy was built with a hand rolled engine. Same for Cave Story, Binding of Isaac, Terraria, Stardew Valley, Dwarf Fortress, Celeste and many other memorable titles.

It's more intense on the Japanese side though. Loads of -doujin- game developers, like the many Touhou spinoffs games handroll their own stuff.

I'd say, using a prebuilt engine ecosystem has become more common with the appearance and growth of Unity but it hasn't stopped people doing their own thing and it certainly hasn't been a solely positive contribution, you criticize elitism in the days when the Steam store pages are flooded by trashy asset flips and barely working early access games that sometimes never truly get finished. A little bit elitism would in fact not hurt if we don't want to hit another video game industry crash.

[Pulcinella]

Stardew Valley and Celeste aren’t entirely custom. They both use XNA.