A year, maybe two.

if I had to rate the worst video game purchase I have ever made.
buying bg3 was it.
I'm old, that is actually quite an achievement.

It would have been good to qualify that statement even though you chose to quote the OP question which you didn't have any intention of answering.

Perhaps you can tell us why this is the worst game you've ever purchased and perhaps give an insight to whether this has anything to do with the fact that it has yet to be completed?

Unless I'm wrong you need to reread there post as

The worst game "purchase"
rather than "the worst game purchased"
They sound like they're regretting spending money on the game rather than saying the game sucks...

Gee it was released October 5th 2020 after starting a few times and losing all I said enough and uninstalled it. So you think getting a release 3-4 years after purchase is ok? Good for you I have a bridge in Brooklyn for sale too. LArian Studios is losing future sales I promise you that.