clay_c@wonder
At least in North America, I would say that the rules governing a highway-railway crossing are more a function of the crossing itself than of the railway line. It's totally possible to have gates at a highway crossing with a streetcar line, as well as unprotected crossings between highways and conventional rail. The characteristics of a crossing don't necessarily imply anything about the rail line itself.

railway=tram_level_crossing etc. originated in countries where there are different laws governing crossings with street railways as opposed to conventional rail. Disputes like these are convincing me more and more that this tagging scheme should be applied to street railways in the US as well.