1) It may turn out that a lot of this is necessary in order to sell B2B and keep half of the software industry going. The business on the sell side might need to reach out multiple times, engage a sales engineer, help you align all the decision makers etc otherwise it simply wouldn’t get done. Buyers are so busy and selling to a big company is so complex that some of this is just a necessary evil for B2B commerce to continue.
2) Imagine if companies were actually better at buying. They spend $millions on enterprise bloatware when startups can literally produce something 10x better at a 10th of the cost. If they were easier to sell to then we could all have nice things without this madness.
I agree that the OPs experience is soul destroying, but clients could help themselves a little and end up with more money in their pockets and better tech.