"which continues to be missing in the Italian wiki you 'corrected'."

Uhm, I didn't "correct" the Wiki with the new codes, that was someone else work: https://wiki.openstreetmap.org/wiki/Special:Contributions/Highlander
I wouldn't edit the Wiki that drastically without fixing all the codes in the database before. Unfortunately the job is done and everything is a mess now.

Unfortunately after this change lot of traffic signs can't be recognized anymore, since they swapped codes, such as in this case that luckily I could fix only because you put the sign type in words in "description". What I did sadly is just 1% of the job, I guess if it wouldn't be better to just use something like "IT:Senso vietato" instead of codes that are not human readable (and also can change or be wrong since years in the wiki, I don't know).