I've had great luck with the cheap Chinese bibs/jerseys I've picked up from Amazon and Aliexpress. I wear and wash each pair once a week (frequent commuting), and they've all lasted well. Biggest problem is some of the whites are starting to look a little dirty. The hardest part was finding kit that's decent looking and "generic" (not a knock-off of pro team or high-end brand).

+1. If you look at the official Assos site you don't see bibs with the name plastered on the thighs.

I agree with Vince. I've had some cheap jerseys as well, and they've lasted pretty good. I can easily get at least 3 years before any issues with the jersey (stitching coming lose or a friend of mine's zipper hook snapping). So, considering you pay $30 for for at least 3 years isn't that bad. I can easily afford to keep multiple jerseys, and wash them only once a week.

I commute to work when weather permits (±30 km each way, 2-4 times a week). If I was buying all $100+ jerseys, I would have to wash them more frequently, and the wear and tear will also start to show.

I have some expensive ones ($100-$200 range) as well, bought on sales from various websites, and the wear and tear starts to show no different from the 'cheap ones'. In fact some of the long tights bought from Nashbar and Ribble are wearing out worse than the ones bought from Ali/eBay.

Why do more expensive jerseys have to be washed more frequently? Do you mean you wouldn't be able to afford to have as many, and would be wearing the same ones more often? There is no point to judging longevity by how long a jersey holds up. It makes more sense to reduce the question to the more basic issue, how many washes will it withstand. Then if the cheap and expensive perform similarly, it is just a matter of what you like and can afford.

Yes, it's a combination of the two.
More expensive jerseys means lesser number of jerseys, and hence the need to wash them more often. So, wearing them more often and washing them more often will wear them out faster as compared to having a larger number of jerseys in stock.

Yes, but more often isn't an issue as the jerseys will have performed as well as desired. It is not about longevity, it is about what you can afford to buy and wear.