I am for creating a new pathway=* tag that includes everything under highway=path and possibly other tags like highway=footway, hwy=steps, hwy=bridleway and hwy=cycleway.
In the remaining months of 2024 we could decide what top-level tags pathway=* would support and give them proper names.
Then starting on January 1st 2025 start a transition period where this pathway=* tag acts as a secondary level tag to highway=* and coexists with it, and ending in December 31st 2029 (for example?) all paths with a pathway=* secondary tag have their top-level highway=* deleted, effectively turning pathway=* into a top-level tag along with highway=*. Any remaining highway=path without a pathway=* tag could become highway=unknown or pathway=unknown.
Then starting on January 1st 2030 all renderers and routers will be forced to have switched to supporting these tags (and they will have had 5 years to have done so)