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Very true. I'd absolutely switch to Mojave if I could, but many of my older apps have issues already on High Sierra and I wouldn't want to make it worse
You've said that a few times as if it's a thing but, since you haven't tried it, you might not want to pound that drum so hard.

Mojave fixed a number of issues in the MacOS — a couple lingering since Leopard broke them way back in the PPC days. Some of my apps performed noticeably better after going to Mojave, Encore being a standout — had been fairly useless over Sierra and High Sierra. None performed worse.

High Sierra broke external GPU functionality with OS 10.13.4 unless over TB3. Anyone using a DisplayLink box over USB (like me) or any eGPU over TB 1/2 was all of a sudden out of luck unless one reverted immediately back to 10.13.3 (which had a few really annoying Finder bugs). This functionality was restored in Mojave but not 10.13.5 or 6.

BIAB 2023 Audiophile, 24/60 Core M2 Mac Studio Ultra/8TB/192GB Sonoma, M1 MBAir, 2012 MBP
Digital Performer 11, LogicPro
Finale27.4, Dorico5, Encore5, SmartScorePro64, Notion6, Overture5