If you want to ship a game, don't write your own engine. End of story.
Save yourself the pain and use Unity instead if your goal is to ship something.
This is especially important to keep in mind when it comes to smaller (be it indie or "AA") developers - the developers who write their own engines aren't trying to replace Unreal, these engines only support a tiny tiny fraction of the functionality that Unreal does and that is fine because that functionality is what these developers need. If anything, for a smaller developer that does not have the necessary developer manpower to mold an existing gargantuan engine like Unreal to their needs it can be a better choice to go with their own engine than try to understand and modify Unreal.
Writing your own engine is never your most important problem as an indie developer nowadays. It's not important at all.
If you have lost sight of that, then you've already failed.
My comment was about responses that compare custom engines with middleware engines-as-products like Unreal and Unity that imply that a custom engine has to provide at least as much as unreal and unity which is certainly not the case.
And my comment wasn't even about indies, this is the case with non-indie studios too - even AAA ones. In fact the previous AAA game i worked at used a custom engine that had zero networking support (outside of some debugging stuff) - because the games that the studio built were single player titles and thus they didn't need such a feature. This is something that an engine-as-a-product like Unreal or Unity cannot do, they have to care about multi player support even if many of the games they'll be used for are single player only, because some of their customers will also need to create multi player games.
It’s comes about because there are lots of people who say they want to make a game who are far more happy eternally twiddling their tech. Moving to Unity/Unreal/PlayCanvas etc. wouldn’t dampen that impulse just push it in different directions. It’s a bit of an empty page problem where it much easier to obsess about having the right starting conditions than it is to actually just start. Particularly as these people tend towards being more technically capable without a lot of design experience.