The way I see it personally is either:
It'll keep going up and eventually my collection will be worth so much that I'd be stupid to not get rid of it (let's say quadruple it's current value perhaps), OR
This is all temporary due to grading, comics people, and/or pandemic related things, and things go back DOWN (potentially even the proverbial "bubble burst"), at which point, nice - I can start buying things more liberally again.
Either way I'm happy. I have my curated collection by and large completed with a few outliers missing here and there, but I'd be satisfied right now if I could never buy another (retro) game due to prices going up.