However, implicit access tags get overwritten by excplicit access tags, else "highway=path, motorcycle=yes" (popular in SEA to exclude them for motorcar) wouldn't work.
The real issue is that the mainstream routers don't even KNOW the highway type "busway" i.e. they can't route bicycles over them because it's invisible to them (akin to how Carto doesn't render them), not that they forbid to route bycicles over them with no way to override access tags for whatever reason.

This is a clear example of tagging for broken routers because highway=busway has been defined two years ago and these roads aren't service roads in the classical sense either as per proposal.

busway=designated also is nonsensical, it's currently defined about the existence of bus lanes than tagging the type of road (and feels redundant with too) and doesn't imply any sort of access right now (basically, I see it as a duplicate of "bus=designated" and should IMO be replaced as such).
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            #REVIEWED_BAD #OSMCHA
            Published using OSMCha: https://osmcha.org/changesets/154411826
            