This isn’t meant to be a discussion on the morality of the embargo, but the affects of the embargo ending for both countries. These affects can be political, economic, or social.
Even during the ‘open’ Obama years, tourism for Americans was severely limited by the lack of banking interchange between US banks and Cuban ATMs and credit card networks. You have to bring cash and use a currency exchange, and if you run out you have no way of getting more money from your American bank. Other countries’ networks don’t have this issue, but it would need to be fixed for Americans to visit and spend money.
I’m glad the internal currencies of CUC vs CUP have been resolved, though a massive influx of tourist dollars would strain the existing economic systems of Cubans being paid for jobs other than tourism.