I always say Kenya is very strategic. The planners of Nairobi transport system knew that without an efficient mass commuter rail system in Nairobi, the BRT would become another bottleneck to deal with. Look at Tanzania who work on impulse, their BRT stations are always crowded like a market and not enough space or capacity.
Kenya delayed BRT implementation by choice, to prioritize MRT which would then be complemented by Mass bus transport to ensure a smooth transition from one to another.
Here is an excerpt from an article by Matteo Rizzo in 2019, on why BRT without MRT have become expensive and even caused riots in some countries.
" Dar es Salaam, in Tanzania, is...home...to DART – the most ambitious BRT system in Africa...Though DART officials pledged that BRT fares would be comparable to those of...the minibuses which provided the cheapest form of public transport in Dar es Salaam before BRT – today, DART fares cost on average 55% more.
This fare inflation is common to BRTs elsewhere in the world, and was even the cause of violent protests in Bogotá, in Colombia...Roughly 70% of Tanzanians live on less than 4,400 Tanzanian shillings a day, (that’s less than US$2). Yet a two-way commute along the main branch of the BRT would cost 1,300 shillings – that’s a staggering 30% of poor people’s daily income...By comparison, the same commute by daladala would have cost 800 shillings"~
Homepage | Business & Human Rights Resource Centre
Now contrast that with Kenya's plan.
i) Do not start with new MRT DMUs like Taipei and buenos aires, which would have cost kshs 10.6 billion for the 14 dmus with an operation lifetime of 30-40 years.
ii) Hold onto the BRT idea but do an MRT first in phases with 11 modern refurbished DMUs that will cost 1.8 billion but with an operation lifetime of 28 years and move 4 million people monthly on existing infrastructure.With each MRT DMU capable of moving 300 people at once at full capacity.
iii) Talk to private sector players to integrate Matatus into the new way of operation in the MRT routes in phase 1.
iv) On completion now introduce mass transit buses(NOT BRT) to shuttle passengers not into the CBD but to and from the railway stations.
essentially what I have described is how transport works even in europe of course without matatus but with mass transit buses. Germany, Denmark, Norway, Finland etc do not have a BRT system, they have an efficient MRT with Mass transit buses picking and dropping passengers at the train stations.