Hi Josh
In my experience, I don't think what you're describing has anything to do with superhost status or season – from the beginning of hosting I've had short-stay guests who've been a bit messy and longer-stay guests who've used all the facilities and been respectful of boundaries. We haven't really had anyone unbearable, but we only have a maximum of 2 guests at a time; four guests and you're multiplying the chances of getting irritated!
I've also noticed my own reactions: when guests first arrive they may be a little tentative, and then gradually use the kitchen more – my first reaction is: “Ah, they're making themselves more at home, great!” And then, after a couple of days, I start to feel rather peeved if I can't use my kitchen freely! TBH, no matter how much I like our guests, there's a part of me that's quite relieved when they leave: “Yay, I can cook when I want!”
NB1 If they're using the kitchen frequently, I would definitely expect them to leave it as they found it. The longer their stay, the stricter we need to be at the beginning.
NB2 There are guests who are using Airbnb as an alternative to permanent accommodation – I'm not saying this is a bad thing, just a fact – a couple of our favourite guests were in that tricky situation but, thankfully, they stayed aware of boundaries. I'd imagine that some long-term guests would get a little too complacent and “revert.”
NB3 Like you, I want to be affordable, and haven't noticed a drop in the quality of guests' behaviour as a consequence.
Maybe you're just having a run of bad'uns... it happens.
Anyway, I hope things get better for you!