This is a bad argument. They are affected by microseconds and kilobytes, in proportions insignificant compared to the memory usage and parsing time already required.
As you're the article author, if you're even remotely interested in being taken seriously (because right now there's less-than-no reason to) it behooves you to actually demonstrate a perf or memory delta that anybody would notice in the first place.
In this particular context, it shouldn't be the developers task to minify code anyway. If the browser engineers deem that there is reasonable speedup to be gained from minifying extensions, then they should do it as part of chain from developer to user.
