Seriously, what the hell is wrong with people in the crypto world?!?
Nothing. People are free to discuss things and free to have ideas. If the consensus will accept them... that's a more complicated story.
However, it's an old idea that came now back to life and it has another form now, not 300k. More exactly:
So Luke's new proposal is actually a way to soft-fork to 600k weight units, which is not at all the same as 300kB.
That's truly bizarre as an idea, apologies to Luke. That would mean keeping the base size at 1MB, and only being able to use 600kB within that base limit. The segwit discount would still reduce fees for segwit tx's, but the incentive to use segwit tx's as a way to boost capacity would disappear if the base size (1MB) was higher than the weigh limit (600kWU). Don't see the rationale for that at all.
From what I see, there will be no consensus for that, but it is, however an interesting read. Just go to
that thread (but please let the devs discuss, since it's a Dev & Tech thread).