The local authorities have been trying something resembling that strategy near me in Cambridge for years. It doesn't work. Even serious research commissioned by the local council a long time ago said it couldn't possibly achieve anything like the stated goals, yet they persist in the folly.

It turns out that buses need effective interchanges to provide anything resembling useful connections. Those require a lot of space for the venue itself that typically is not available. They also require extremely high connectivity into and out of that venue, which is typically not how existing roads are configured.

It also turns out that buses block up normal-width two-lane roads every time they stop. The amount of interference between just the buses themselves grows far faster than the number of buses on the road, because it is very difficult for them to pass each other when one is at a stop. They similarly cause obstructions to other road users in large motorised vehicles, including delivery vehicles and emergency services. And they force smaller, less visible and more vulnerable road users like cyclists, motorcyclists and crossing pedestrians into relatively dangerous situations when passing or crossing near them.

Buses are efficient in terms of fuel/environmental considerations only in situations where there is a critical mass of passengers wanting to travel on the same route at the same time, which you do have in big cities like London and Paris, but don't in smaller ones. That leads to either having little or no service where there is less demand or running large vehicles that are actually less efficient than smaller private transport on a lot of routes outside of peak times.

Bus journeys are inevitably very slow compared to private transport, because of the circuitous routes, frequent stops, large and slow vehicles, and often some extra time walking to and from the stop at each end of the journey. A typical journey by bus can easily take 2-4x as long as it would by car and may be little faster than walking and much slower than cycling at congested times.

Buses lack flexibility, particularly for passengers carrying large amounts of baggage, unwieldy items like pushchairs, or themselves disabled and travelling with equipment like wheelchairs. Often there is not enough space on the bus if more than one or two people with extra things with them want to travel at once, and stories of people having to wait two or even three buses before they could get on are not unusual.

Buses are horribly unhygienic compared to any form of private transportation, particularly in colder months when often there is little ventilation and lots of passengers generously sharing all of their bugs with everyone else aboard.

Buses are less comfortable than almost any form of private transportation.

Basically, buses suck. They may be somewhat more space and fuel efficient under ideal conditions, which often do not exist, and what advantages they do have in those respects are often mitigated or cancelled out by their numerous downsides. Almost any imaginable transport system, public or private, from simple walking and cycling to high-tech underground metro systems, is better than buses. Buses are awful.