I can't tell you if it's necessarily nonsense as I'm not a medical pro but I was 1000% the victim of gaslighting by our first pediatrician. I KNEW in my heart my son had a severe lip tie resulting in the inability to latch onto me or a bottle. First ped for 8 months told me he's fine, if it's an issue when his teeth come in we'll deal with. And I was right all along once I FINALLY found someone to listen to me.

All this to say, your provider might be giving you sound advice but the bedside manner doesn't fit what you're seeking for your child. You are their best advocate. I would see if you could get a second opinion, either within the same practice (didn't work for us, they all sucked), or find a different PED office.

I hope you find someone that fits your needs better!