The coaches from Kent to Docklands and the City did OK until lockdowns and working from home became a thing I believe. Those from North Somerset to the north Bristol fringe didn't.
The Cambridge 'misguided busway' has been said to have a dedicated right of way where it doesn't need one but not where it does.
That being a common problem. Build / paint a bus lane, not where it is needed but where there is plenty of road space and little traffic!
BRT is the better answer but that requires a large capital investment and probably demolishing large chunks of a city to fit it in. I've briefly looked at several. Dar es Salaam has one where the stops are widely spaced and are substantial affairs, not dissimilar to an LRT or heavy rail stop ie several bus lengths of platform and with overtaking lanes for buses. They have feeder 'minibus' routes connecting areas to the trunk BRT routes. Lagos has a similar network but, like all things Nigerian seem to be, it is chaotic. Nairobi has one under construction.
Somewhere there is a table showing the relative carrying capacities of traditional bus, BRT etc. All three of those African cities actually need proper LRT/Metro/heavy rail solutions given their size, population density and congestion issues.
Google Streetview will reveal all.
Stick this into the Google maps search bar -1.281321225538098, 36.82264650972426 - Koja bus terminal looks sort of reasonable on aerial, then flick to Streetview and look from all angles!
This location -1.286640347604315, 36.82875695963487 is the main bus station, once home to Stagecoach Kenya part of the Stagecoach we all know and love.
This location is the outer terminus of the main Dar es Salaam BRT route -6.787056822865243, 39.16688417154883 follow the route for a feel of the scale etc
This location is the outer terminus of the main Lagos BRT route 6.621178966684949, 3.502175512852991