Those cultural issues - greed, rent-seeking, etc - are not unique to Africa. They all describe subsistence businesses that join the beaten path. Hotel, retail and such business - face cut-throat competition. The lack of demand is driven by competition with no differentiation. Such businesses would not significantly transform the economy even where successful. The overwhelming majority of Kenyans are employed by MSMEs. It is disingenious to claim the same MSMEs don't survive let alone thrive.
Inventive business models - startups - are businesses that solve real problems. M-KOPA Solar, BRCK, One Acre Fund, SunCulture, Uber and such. Not duka or hotel or real estate - which just slice the pie and not grow it - so they are not even considered startups. Startups rarely have serious competition - because of their uniqueness - solving the unsolved problems. They create new wealth, jobs, taxes, etc.
It is these risky capital- and talent-intensive innovative enterprise capabilities Kenya and most Africa lack.