I agree that we have no idea if he'd actually go through with reforming the court if given the opportunity - I'm just pointing out that Democrats have openly called for reforming the court, on the presidential debate stage, as recently as 2019. It shouldn't be viewed as a non-starter - especially when these ideas were coming from the so-called moderate wing of the party.
On the M4A topic, it's crazy to me how its supporters have managed to ally themselves with the private healthcare lobby in opposing a competitive public option. If Medicare is more efficient than profit-driven insurance, as we all suspect, then forcing private insurance to compete with it puts us on a direct path to a single-payer system. Pete is a democratic capitalist - it shouldn't be a surprise that his version of M4A uses the system in place to get us there. If Bernie amended his bill to include a 15-year transition plan I doubt anyone would accuse him of flip-flopping.
To be fair I think it's too early in Pete's political career for me to say that he stands by what he says or for you to say that he doesn't. I don't think anyone can hold a candle to Bernie on ideological consistency - he would rather lose than compromise. We all admire him for that, but it makes him a better activist than politician. I say this as someone who donated to his campaign and voted for him twice.
I agree that Pete is the polar opposite, but I don't know if it's a bad thing. Early on he said that he wanted the primaries to be a debate of ideas, and that - if nominated - he would champion the platform of the party. That could be the MO of a grifter, or it could be someone who's serious about restoring democracy. I don't blame anyone for being skeptical, but if we're dismissing him because we have concerns about his healthcare plan, I'd say we're still living in 2016.