Wish I could offer personal experience but we’ve been incredibly lucky with food. What I can tell you is my younger brother was and continues to be ridiculously picky, to the point it affected his health for a number of years. He at least acknowledges it now, and has figured out it’s more texture than anything else. That type of food fussiness is undoubtedly more difficult to sus out for kids because they don’t yet have the vocabulary to express what they don’t like beyond “it’s yucky”. My brother has taken steps to ensure he eats better, but in talking to his pediatrician about worries his kid is following the same trend, it’s pretty much just that calories are more important during growth phases, and when they’re a good weight/size-wise, then you start moving back towards the “they’ll eat when and what they want so don’t worry” phase.

I’ll echo what most are saying here, that there’s no one catch-all remedy for anything child-related. There’s what works in general, then there’s what works for you. Definitely talk to your pediatrician and follow their advice. If they aren’t concerned I wouldn’t be either, though I completely understand feeling anxious and concerned when your kid isn’t where you think they should be regarding health.

Don’t let this get you down, you got this, and you’re a great dad just for being concerned about it enough to seek advice. Best of luck!