The hate is likely due in part to people like Icstor, DarkCookie, and UberPie. Devs who used to make consistent updates that began to slow down as they made more and more money. We're a couple of weeks shy of it having been seven months since the last update of What a Legend, people are bound to become impatient and there exists tons of examples of devs who started to take advantage of the patreon system after a year or so of regular updates. No patreon developer is above reproach.
I get what you mean, but the whole mental process behind that kind of behavior you're describing is just silly and extremely unfair, especially coming from pirate forum users. First, the milking issue. Nobody is forcing patrons to keep paying a monthly fee when there's nothing new to download, yet they freely choose to keep supporting the dev; this can only mean they are happy with the way dev is doing things and are satisfied enough with what they're getting in exchange (or have gotten in the past). So not really a reason to complain when you personally aren't paying a dime: if anything, complaining only shows your selfishness for not being able to play for free something you like at the pace you'd like to. Now, of course there are devs who lie to their patrons. That's totally unacceptable and unprofessional, and it's fine to warn potential patrons of what are they risking if they choose to still support that dev. But it's not fair to use those blatant cases to raise doubts about every other dev. That's a toxic attitude.
Then, leaving aside those obvious milkers that actually exist (and are way less numerous than you may believe just from reading these forums). From a general perspective, why a honest dev can't take advantage of their past work and earn some money with it? Why can't they try to monetize their own work the way they want? Are they less honest for deciding not to work 15 hours a day just to push the new update a couple of weeks earlier? Why can't they enjoy a comfortable schedule? I just don't see people shitting at Lamborghini for making just a few cars per year and selling them clearly overpriced when other brands can sell millions of units per year: no one goes to the Lamborghini's factory to tell them 'hey guys, your cars are amazing but you should produce more of them and sell them way cheaper, you lazy milkers!' You don't even see such criticism on the internet, it just doesn't happen: you like their cars, you just assume they are not made for you, you just walk away. But, for some reason, shitting on game development is fair game.
Now, coming to this particular case, I can't think of any valid reason to criticize Magicnuts. They offer their game totally free just one day after releasing it for patrons, and their 7 months development time seems reasonable considering the amount and quality of those updates: you can't take the last update and honestly say that you don't believe the only artist in the team has worked 7 days per week during at least 3 months, as they said she did. It's obvious they have worked all that time, they have not delivered a piano simulator. They are transparent and communicative over the whole development process. I do want their game to be updated more frequently, but it seems they just can't do it faster if they want to keep this level of quality, which we all want too. So I just patiently wait.
edit- typos