Yes, and under that proposal, the 1MB limit can remain until Lightning begins to soak up some transactions. You can't make a real case for 2MB until the true capacity of operational Lightning is observed in the real world, I think that's reasonable.
Why increase the 1MB size if blocks became more empty than they are now after Lightning is available? I think most sensible people in cryptocurrencies recognise that full blocks are an important requirement for getting the miner/user incentives properly aligned for establishing fees.
I do not like speculating like this on important issue. There is no way to tell exactly how much of the TX volume LN would acquire in a week, month, in a year. On-chain scalability should not be based on speculative patterns but rather past patterns (e.g. once there is a history of LN usage, then factor that in as well). Besides, LN is not a close reality yet. It's currently being tested, and it doesn't even have a GUI (from what I've seen). It's far from being part of the main-net and even further away from being consumer friendly.
On the other side, BU is speculating on this "emergent consensus" pseudo-science.