Human power unfortunately is prohibitted in some situations and I think justifiably so.
I have been through a number of bridges that require passage
under power. Sail is not safe as the winds are not always steady and reliable and many bridges block or alter the wind
flow. Bridges also often narrow the waterway accelerating the current
under the bridge.
I have seen plenty of boats even with power get in trouble under a bridge. You lose control under a bridge you could block the bridge, damage the bridge, damage the lifting or turning mechanism and block traffic (marine and road if a lift
Similar concerns in canals.
Bottom line, like it or not, boating
with no power or inadequate power can restrict some of the places you can go.