An Update on this, I meant to post a week or so ago but time slipped away from me.
Update: I've decided ultimately to turn off Encryption. Even if I did manage to symlink redirect hack the Joplin installation to another drive, the multiplicative size increase still poses problems for other devices (laptop, mobile) that don't have the capabilities of adding additional drives easily.
The decryption process with the desktop application was painfully slow, now taking at least 3 days. Ironically I believe the original encryption process took only 1 day, 2 at most. While obviously, at this point I'm not a stranger to having long wait times in Joplin, it does feel like this pipeline is drastically unoptimized for speed. I'm curious what the possible bottleneck here could even be, since my light googling on the matter has suggested encrypting the entire 20gb at base64 should take possibly only a couple minutes on modern hardware.
I would absolutely kill for some sort of progress indicator here, because all I get is the "Updated remote items: #" counter slowly ticking up, which is an extremely unreliable source for progress since the goal number always just rises higher once reached. After a day or so of this going in, its really difficult for anyone non-technical to understand what exactly is going on.
It's also impossible to get a sense of the scale of time required until after I've already finished it (which is a main reason why I wanted to post and report this, for anyone else ever considering doing this). Something along the lines of "Encrypting/Decrypting Items Remaining: #" would be tremendous.
This process is not terribly user friendly, and after seeing other posts share similar sentiments I can kinda see why this has some hesitations for enabling still. I definitely would not recommend enabling it without considerable thought first.
The most teeth-grinding part of this is the fact after disabling encryption, the CRYPTED files are left behind in resources to wastefully eat up disk space, which in this case is 20gb of wasted space. I would only know from this discussion in here (and searching the forums) that it would be possibly safe to remove these after disabling it. This is pretty serious in terms of wasteful operation I'm afraid, there's no way to really beat around the bush there.
I'm still aiming to stick with Joplin, but this has definitely been one of the hiccups that have made me question it.