It is a systemic threat because he can't push his own agenda. He's just wasting more time. This does not help anyone.
Disagree. The most influential Core devs want to use the block size limit as a production quota, forcing fees up (and some TXs/users out), partly to focus the minds of devs on other solutions. They have said as much.
The limit was never intended for that and there has never been any discussion or BIP or similar relating to this _completely new policy_. Put another way, there would have been near zero support for a hard limit production quota if they had to introduce it via a BIP.
Also, how is he "wasting more time"? We have to sit around and wait for SegWit anyway, which is at least a month away. We can't do anything about that.
The limit is there because resources are limited, and no limit would lead to massive node centralization. We have data that shows raising the block size now would not be a good idea. SegWit will buy us some time, then we can start considering a blocksize rise, always having in mind that scaling bitcoin worldwide without an additional layer is impossible without mass centralization on the nodes.