This is kind of... Not a good way to look at it? Obsessive perfectionalism doesn't a fun D&D experience make
Mistakes happen and its fine to say "Yeah that spell you used should have been 2d8 rather than 2d6, sorry, we'll fix it going forward". That's just, normal gameplay and doesn't make some "rulings are now inconsistent with one another!" problem. Going back and retconning to the first fight the spell was used to re-play all of the fights is absolutely overkill and I'd actually just laugh in your face if you suggested it.
I genuinely cannot see a world where anyone cares about the inconsistent rule thing, or if they do, is a player I want to keep around
If something's a bad enough situation I'm talking to you out of character about it and you tell me to deal with it in character, we're not going to be friends for much longer and someone isn't being invited back to next week, be it the player or the DM.
"Its what my character would do" is a one way road to a terrible story on creative writing sub r/rpghorrorstories, not something I should be putting up with.