Those statements can be easily countered.
1. Take almost every politician. Also, what is a promise? Does every statement L&P gives is a promise? If so then you sound like my kids - "but dady, you promised we'll go fishing this sunday" when all I said was maybe. And if by promise you mean the goal tiers, then as far as we can tell he fulfilled them, maybe not to our full satisfaction, but he did (face lift to his rig - twice, quit his side job - probably, otherwise it would have been harder to leave the country, and find helpers - even if you don't believe he has an animations helper, it's obvious he has someone helping with programming and testing, and he has a translator - that's helpers, even if we wanted daz helpers...).
And what about "finish his job properly"? What exactly is, and who decides what's proper? It's subjective - what's proper to my eyes can be improper to your eyes and vice versa. It's each and every Patreon of him to decide whether something is proper.
2. It's not up to me to prove he isn't milking (I can't), but it is up to you to prove he is if you claim he is a milker (unless you know him personally - you can't also). For more information why - read
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. As for why you can't prove it - that's easy. There are many valid answers to the question "why is he so slow" (although there are many slower developers than him, some even earn more money). And if you think he's a milker because he only tease with Sophia, then maybe it's better you read his Patreon page - he said it on day 1 - that's a slow corruption game. He even gave us a roadmap for sex scenes. If you haven't read it - don't blame him.
3. "The story is less probable"? Not in my opinion (the whole promise of an educated character as Sophia having an incest affair(s) is very improbable in my opinion). As for "even the coherence is broken" - it has been already discussed in another post - the story is a work in progress. As long as he'll polish old parts of the VN to be consisted with new parts, I don't see a problem here. whether we like the new changes or not is irrelevant. It's his story to tell and he can change it as much as he want (and as long as the majority of his Patreons are ok with it).
4. "The game is old"? what? why? how is it relevant? If it has enough supporters, and I'll even argue and say - if it has enough fans - than it isn't too old. Interest in this VN is still in the top 10%, so in my definition it isn't old. If someone has a different definition and believe this game is old - good for him. I know what I'll do when this game gets old in my view - I'll just leave it behind, just as I don't play Packman and many other old games anymore.
And just a disclaimer - I don't like L&P's development pace and really wished it was faster.