I’m looking for a list of all deprecated tags related to new tags to search on a large region so I can change them and notify mappers who have recently used it that the tag has changed or been dropped. This would also allow to update the map (I promise, no mass edit).
I would kindly suggest that you 1st read up on the concept of deprecation in OSM (and its misuse of late) before you start doing what you are proposing, otherwise you might be quite surprised by the reactions.
True, but then again, nothing is perfect. But it is not so bad overall (i.e. most of it makes sense).
Interested parties should consult multiple sources and decide that something is really deprecated only if many of them agree. So iD, JOSM, wiki of the tag, its talk page, accepted proposal for deprecation, tagging ML / forum discussions etc.
If only one claims something is deprecated, that should be taken with huge grain of salt.
What goes into the Wiki is not vetted. In regular intervals, over-eager individuals take it upon themselves to “improve” the Wiki and “clarify” things without consultation, creating misleading or plain wrong information. Even when there is a “vote” on something, it’s usually just 20 or 30 people voting, compared to thousands who might be using a tag. That’s why you need to be very careful. You can certainly ask someone whether they are using tag X for a particular reason now that tag Y is a more common expression of the same concept. But any wording that implies their tagging is “outdated” or even “wrong”, or that they need to change because the Wiki says so, is certain to meet with opposition - especially if you are not a frequent user of the tag in question yourself and lack any subject matter knowledge!
One thing that you can do with a list of “deprecated” tags is to look for data consumers who are looking at the “old” form of a tag but not the “new” one.
Taginfo.osm.org has a “projects” tab where you can see what projects handle what tags. If the “new” tag is seeing significant usage and they are not aware of it it might be helpful to let them know that it exists.
Of course, there may be reasons why a particular data consumer does not want to use a particular tag - if that project has an issues list at e.g. GitHub you could see if it has already been mentioned.
Be aware though that this list covers only some project using the tag - do not assume that if a tag is listed there by only say 3 projects that there are only 3 projects using that tag (i.e. it only means that there are no less than 3 projects using it. There could 30 or 300 of projects using it)