We discussed this some time ago. Solution was to tag both. In case of only slight deviations, the “right” RTGS is in name:en and the sign-posted one in alt_name:en. If it is a completely made-up transliteration, which happened sometimes, then the sign-content was in name:en and the correct one on alt_name:en. This was it is possible to find it, for example using nominatim.
Keep in mind, that we are not speaking about the official name, which is always in Thai script in the name tag. It is about the latin script transliteration/translation for foreigners.
I changed the proposal now to use the tag is_signed:* now based on the feedback. has_signage:* was also mentioned, but the former has been mentioned more and noone commented that either sounded odd, so .
Since the proposal received quite some comments and feedback already here in the forum, I do not think it is necessary to prolong the RFC phase, so I set the voting to start mid this month end and end at the first day of March.
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