Wrong yet again. Money is a huge incentive to create, which is why he abandoned his comics and started doing this game in the first place.
Anyway, you're acting as if this would take a huge amount of skill. As far as I know, SR7 mainly uses Unity plugins for the code, and doesn't really write anything himself. So the fact that every update is this buggy is inexcusable. The fact that every update gets smaller and buggier is also inexcusable.
His art is good, but he mainly uses interchangeable assets that don't take a lot of time to edit. So it's really the poor code that keeps him back. And laziness.
Money is an incentive but won't make anyone more skilled overnight. If he's not a good programmer and uses only Unity plugins as you say then this amount of bugs is even surprisingly low. And if he is not a programmer then you shouldn't expect him to have bug-free builds, it's unreasonable. Even AAA titles are constantly shipped bugged and they have very good programmers and big teams to boot. So you're hurting your cause even more with this argument.
People pledge because they like the game, both in concept and what's been done and also for what could be done in the future, but no amount of money pledged can justify the expectation of a technically good product if he is no programmer, doesn't have one on the team and hasn't promised to get one. If he got someone else on board or said he would, you might be right about patrons possibly expecting better quality, but if not then it's just a willfull wish.
About the art being reusable assets, it doesn't matter, the patrons sure find it worth enough to pledge.
You just don't like how much money he makes because you don't feel like he deserves it, but in the case you were right the patrons would simply stop or decrease their pledges and in time the money/worth ratio would normalize.
So, unless you want to make an argument for people to stop or decrease pledging, thus possibly halting the game's development, I don't understand what your goal is, apart from some kind of dev-shaming of sorts.