You can more than one even on the base max plan. So 100 USD gets you started.

Started yes, but in the long term?

You cannot ask this follow-up unless you first answer mine as to cost. And not cost today but cost for the long haul.

the cost is $7bn - is that too much if it generates $10bn in revenue?

This is known as question begging; the question is: Do the costs justify the investments? That question can't be answered by assuming they do. Also revenue is not profit.