I personally am disappointed that there's so little will to improve buses. Buses have a lot of good attributes:
1. Turn radius is pretty good: streetcars have 18-20m turn radiuses, buses are comfortable at 12m radius, doable at 9m, and can go lower. Buses are compatible with existing city forms.
2. Because of this you can change routes based on demand. This almost never happens, but it should.
3. Broken buses don't break the line.
4. Express buses can coexist with local service buses.
5. Turns out passing is a useful feature!
6. It would be possible to responsively add buses to meet demand. Never happens, but possible.
7. Variable stop frequency is a possibility. If you are on a late-night bus in New York they'll let you off at any corner you want. (Most cities lack this basic sense of decency, but I won't claim we do buses right.)
8. The vehicles are not proprietary. You don't like your buses? Buy any brand you like!
9. New manufactures could enter the market. Trains are regulated to a degree that makes it very difficult to enter the market. This is especially bad in the U.S., so maybe it's unfair: we have terrible regulation, and local manufacture requirements. This has a lot to do with the high subsidies trains require: it requires so much political will that everyone wants a piece of the pie.
10. Buses don't have to be inefficient. Intercity buses are often more fuel-efficient than intercity trains, for instance (I'm guessing this is mostly because they use variable pricing to run at capacity, but something like that is possible for transit too.)
11. Rubber wheels are pretty awesome for stopping, and stopping is pretty awesome for not killing people. Trains are incompatible with humans and even cars except at very low speeds, and require intense separation, or barriers with long lengths of times to let traffic and pedestrians clear. Surface trains substantially hurt the walkability of their immediate surroundings.
12. Buses can run lines that are more dense than trains, which is important for people with disabilities. Most disabled people I see are using buses.
13. We really do need roads everywhere. I remember making SimCity cities with only trains, but that's not a real thing. You need roads for emergency vehicles, trash collection, utilities and utility repair, your moving truck, and so on. I'd love to see roads scaled back, but they aren't going to disappear, so let's make the best of them.
Buses do absolutely suck. But I am not convinced they have to suck. Unfortunately transit systems (buses or trains) have no incentive to meet customer demand, their real customers are the government not the riders. Riders are a liability for transit systems, and so there's painfully little innovation.