Considering that their patron number has doubled after announcing of a multiplayer mode
It's questionable if that had to do with the multiplayer, or simply with the project as a whole gaining more popularity.
And that's still not an excuse for taking a big, fat shit on the other 50% of people that supported the project from the beginning, which isn't even the first time they've pulled a similar stunt either, since they threw the guys that paid for the non-monster first iteration of the game under the bus when they switched development over to the Lovecraft one.
Just as a reminder, the devs themselves basically stated that the MP would be dead without forced content exclusivity. My only hope for this dumpster fire now is that the devs see reason post-release and reintegrate both the NSFW and MP-exclusive content into one game, but that's unlikely to happen.
Oh, and this is just the cherry-on-top:
We will convert all your historically pledged tiers into Likes (the currency in Harem Mode) when the Paralogue goes online to give you a head start, and active Patron supporters will continue receiving bonus every month such as pose packs and vouchers. Although none of these rewards are paywalled in the game, we hope this can be a meaningful way to show how grateful we are for your heartwarming love and support. [Emphasis mine]
Well, now I know why they're pushing the MP so hard - they're trying to monetize the shit out of it. And yes, they do say "none will be paywalled", but nothing is paywalled in War Thunder either, you're just incentivized to hand over money so you don't have to grind. At least War Thunder doesn't ask you to pay upfront for the privilege of doing so.