Everyone told me "use Unity" "the biggest mistake you can make is building your own engine". How well did that advice age? Nobody needs Unity or Unreal. My most recent game (playshadowvane.com) is built on 100% proprietary technology, I built everything in-house down to the physics. Always ignore mainstream game dev advice, they are just trying to sell you products. Build as much as you can in-house, it's not only be…
Same applies to most software. It isn't that hard to make a new programming language or a http framework. But once you make one finding other people who know how to use it is a pain in the ass.