I was going through some older problems in the community today, and I was shocked to see that your topic hadn't gotten a response from us yet. I'm so sorry we let this slip through the cracks - it's truly embarrassing.
As you mentioned, our system currently strips out non-alphanumeric characters from tags. I've reached out to our product team to get some additional information about this feature and hope to have some more information for you Monday at the latest.
Again, my sincere apologies for neglecting your topic for so long.