Get some employees, have some of them turn out to be pain in the ass, then find out how annoying west coast labor laws are.

Hire some employees, spread them across multiple states, find out the complexities of employment law in multiple states.

Start up a health plan, same thing.

There a million examples, none of them are bad by themselves, but every aspect of a multi employee business has rules and regulations that if you run afoul of, there are consequences. No one gives you a manual of these, you find them out along the way and it costs you money and time.

Maybe the OP hadn't in mind the actual process of incorporating a company per se, but the process of "starting" a company as in getting it off the ground in terms of money coming in/revenues. And, imo, it's more difficult now to do that compared to 10, 20 years ago, and not only because of increased competition.