He did not just "exploited this uncertainty to pervert the meaning just for lulz". If you have read any of what Luke-Jr has said about block sizes and capacity, he genuinely believes that the block size is currently too large because it is difficult to start running a new full node. It is also becoming unsustainable to continue to run a full node since it costs so much in bandwidth, processing power, RAM, and disk space. It wasn't proposed "just for lulz" or to troll anyone but rather because Luke-Jr genuinely thinks that decreasing the block size would help Bitcoin by allowing more people to run full nodes.
I'm aware of his position, but we also know that Luke is certainly familiar with current situation, and proposing something that has no even remote chance of being accepted, especially in the context of fulfilling such important, unique in it's kind agreement is for lulz at best. How big blockers should perceive this? They thought they are dealing with serious people and got such mockery instead.
A lot of that is because they think that having a 2 MB base block size is too large (that means that witness block sizes can go up to 8 MB).
Big blockers want 2MB base size. If we think that 8MB max total size is too much, it's possible to adjust parameters to decrease it to 4MB according to the agreement.
Additionally, since it is a hard fork, there are a number of other things that should be included into it as we don't want to have multiple hard forks but rather one with everything that we want that needs hard forking. Segwit2MB does not address that.
Then help Sergio to integrate all desired improvements. Announce that we are working on a hardfork which includes increasing base blockse to 2MB and a number of other improvements. Apologize for being late with that.
What do we want? To prove to our opponents that our point of view is the only right one? Or to finally scale?