Often you will spend pointless time just doing this circus. So much so you would be rather better off, directly working hard on the main exam.
Start ups are hard, you will likely fail certainly. In all that work there is to do. And all that stress, anxiety and tension you are likely to go on merely working on your start up. I wonder what is the point in taking all the pain to fight for a Visa amidst all this(Which you are very likely not to get).
There is no doubt there are amazing benefits of working in the USA. I would do anything to get an opportunity to work in the United States. But to get a H1-B(Or any work related visa) is a great challenge, especially for guys like me. Plus years of living under perennial threat of getting fired, losing your job, having to restart your green card process all over again(If you've started), and redoing all of this if you lose your job all over again, spending decades doing this and chasing sub goals. At some point you have to wonder, if its all worth it.
Why not spare yourself the pain. And work on the actual thing itself.