But we can't also prove that there is no flaw either, and I personally WON'T gamble my Bitcoin savings on it by storing them in a hardware wallet that has closed source firmware. I'll probably use it for shitcoining very small amounts of Bitcoin through Magic Eden Runes market merely because I have already ordered it. But if I remembered this topic before I purchased it, I probably will not buy it.
Your way of thinking is exactly right.
Even if there isn't a flaw, there's no way to know if Ledger will leak their code again, giving hackers the chance to reverse engineer it. And there's no way to know if a future firmware update will introduce a bug that could give hackers access.
With closed source code, there are too many unknowns.
And after a company lies to their users, there's no way to trust them.
I learned another lesson, the HARD WAY.
But you learned it, which makes you wiser than those who never do.