While the current automatic capitalization of common names works quite fine for English language and as I understand the previous discussion about correct formatting of English names of certain taxonomic ranks and groups was rather difficult, I’d like to open discussion regarding some other languages that have pretty straightforward rules that should be easy to implement and would improve experience for some non-English speaking users.
In Czech language the best action would be to show name with only the first letter in upper case, without formatting the rest of the text, or use no formatting at all. The species names of animals, plants and fungi in Czech are mostly binominal, with genus names first (often shared across multiple close genera) and adjective species name second. For example name for violet ground beetle (Carabus violaceus) is stored in iNaturalist as “střevlík fialový” and could be displayed either as “Střevlík fialový” if used in title, search results and so on, or just “střevlík fialový” (but not “Střevlík Fialový”!). There might be uppercase letter in second (species) name when species is named after person, for example “Střevlík Linnéův” for Carabus linnaei, so it is not possible to automatically lowercase rest of the name.
Capitalization of first letter based on language should be easy to implement (even when dealing with some special characters). Same approach can be applied to Slovak language (ex “Bystruška fialová”), Polish (ex “Biegacz fioletowy”) and probably some other especially Slavic languages. At least the Czech names in iNaturalist are mostly imported from relatively reliable source and are already in uniform format.