Those messages are ugly and have no relevance to third party users of Wikipedia content.
They have relevance to Wikipedians and prospective Wikipedians. I doubt they greatly annoy anyone else. Some of them could certainly do with a little prettifying, though.
We also do not have a problem with attracting new editors as is so this is a solution in search of a problem.
The existence of a problem is not a logical prerequisite for the desire to improve a situation. We can always use more editors.
Regards, Haukur