Because it's not obviously a flaw, and since it's not obvious you'll have to supply arguments if you want people to believe it's a major flaw. QUIC is supposed

Because it's not obviously a flaw, and since it's not obvious you'll have to supply arguments if you want people to believe it's a major flaw. QUIC is supposed to send fewer packets for the same payload, at least that's what I've heard. I don't follow it closely. Assuming that's true, if you want people to believe that QUIC packets are bigger and that the increased size more than compensates for their reduced number, you'll have to supply arguments. Packet traces for a few typical connections would be good arguments. Assuming it's false, you'll need much the same kind of argument. (FYI I've written ten RFCs and like to think I've learned the RFC processes by now.)