It's all a bit chicken-and-egg. The more people that use a public transport network, the more economic it becomes to put on more frequent services and additional routes. A town of 100k people is more than enough to sustain a pretty comprehensive public transport network, if most of them are using it. But obviously if most people don't use it, those that do are stuck with whatever can be made to work.

I live in a much larger city and this is true. I can drive my car to work in about 12-15 mins or it would take roughly 1.5-2 hours to walk or take a bus. When traffic was low due to Covid I nearly bought an e-bike because I could get to work in about 30 mins. If I tried that now I would certainly be hit by a car in a month or less.

And the trains/busses absolutely have to show up at these intervals to make them attractive and viable for most people, which means that for significant portions of the day they're basically going around empty.