My experience with cheap bike shorts is that they work out so rarely that in the end they don't save me any money, and waste a lot of my time
I cannot count how many times I have succumbed to the recommendation of people on this or other bike sites about some awesome $25 bike short, only to either immediately return it after trying them on, or go ahead and give them a try, and regret doing so (I am not about to return used bike shorts).
Some aspects of road/gravel cycling I am willing to go super cheap (glasses, shirts), others aspects it just needs to be half-decent and functional (pretty much the entire bike), but a few I want the good stuff and I am willing to pay for it (tires, shorts).