He's not a picky eater. He's a dicky eater.
First, I just had to add that this totally made me LOL. That was SO my DD (only kid in the 2-yr-old room who had to be strapped into a high chair to eat, because otherwise she'd run around and talk to her friends and be totally exhausted/starving melting down later).
I don't really have much helpful to add; sounds like you're doing the stuff I'd have suggested. One final thought: could it be that the toddler is picking up on your frustration and is therefore on edge and is therefore acting out more? I know when my DD was that age, she was my little stress canary in the coal mine -- if she was acting up more than usual, I'd sit and think about what
I had going on, and I'd almost always realize that I was stressed out from other stuff, and she had picked up on that before I had. Kids are really, really,
really attuned to their parents' emotions, and your (totally natural) frustration might unfortunately be feeding the cycle.
Or it could just be a developmental phase; kids tend to basically lose their shit right before a big developmental jump.
The one thing I'd urge you to (try to) keep in mind is that kids most desperately need love when they are the most unlovable. He doesn't like feeling and behaving that way, either; he just doesn't know any better way to manage whatever those big emotions are that he is feeling. And you really, really don't need to worry about spoiling him; from everything you've written here, you are exactly the kind of parent who is going to navigate this and have reasonable boundaries and expectations. So if he needs a little extra cuddling or attention, even when he's most definnitely being unlovable, feel free to try out being extra lovey without worrying that you're now setting him on the path to permanent entitled twitdom.
Is there something you can do to break the cycle, just shake things up -- for him
and you? Just to change the narrative? Maybe everyone leave the table and lunch is over when the whining starts -- "oh, ok, you must not be hungry now, we'll eat later" -- and now you go have an unscheduled story time or walk instead? (Ignoring the ensuing tantrum, of course). FWIW, my favorite "consequence" was always naptime -- "oh, wow, you must be really tired if you're having a fit, because I know you're way too big to act like that. Sounds like it's time for a nap." (Didn't actually work that much -- at least not right away -- because the emotions were way bigger than the prefrontal cortex could manage. But over a couple of years it did. And it also gave me something to say that kept me from losing my shit).
But what the hell do I know -- my DD was atrocious at that age, because I had my little statistical outlier first and my "normal" kid second, and so I did everything wrong. But I will say that the things I regret now are all the times I lost my patience and became discipline-ary, instead of really seeing that my kid was just as freaked out by how strong her emotions are as I was annoyed by it.
Also: he's not going to shut up. He just won't. That's not what kids do. Is there anything you can do to give
yourself a break or change of scenery so the inevitable annoyances just slide off you like Teflon?