If the concept is appealing to you it could also mean that Factorio itself doesn’t suit you. For example I find the concept appealing and I did put a fair bit of time into Factorio, but in the end it just didn’t click. But I loved playing through Satisfactory and I’m currently playing through Techtonica which I’m also enjoying. Maybe one day I’ll learn to love Factorio but in the mean time there are other factory builders that I’m enjoying.
To be honest, I also can’t fathom it being such a massive flop. On Steam it peaked at 700 players. Shadows of doubt release peaked at 2200. Something had to go seriously wrong when a niche indie title with no mainstream appeal has a better launch than a AAA game. I don’t think it should’ve been a success, but it definitely should’ve done better than that.