Honestly I think you're overthinking it lol. My main scoby is like a thick rubber mat and my brews are totally fine, maybe even faster. That big mass of cellulose is just more surface area for the good bacteria to work. If it was eating all the sugar you'd see way weaker fermentation, but my bottles still get plenty fizzy. I've never trimmed mine and my brew times have stayed the same for two years.

That leather cup trick @brooke_walker23 mentioned is solid, but a cracked graphite piston ring can cause the same issue and needs a different fix.

Yeah, the ammonia trick is no joke! I tried it once on an old vise and nearly passed out from the smell in my tiny garage. My wife thought I'd started a secret chemistry lab out there. It did work, but now I just use a torch and oil like ruby494 said. Less chance of me accidentally gassing myself, which is always a plus.