I'm American and I went!
It's not too bad actually. There's a bunch of rules technically (all imposed by the American govt because they think they can control what you do abroad...) but really it's not to hard to follow. Have to stay in a Casa Particular instead of a hotel (because the hotels are state run), which basically means get an AirBnB. Prices are very affordable. I paid $100 for a week in Old Havana. Flights from Florida were very cheap. Then you have to avoid government run things. I found some private tour guides for some trips outside of Havana but most days we just took taxis or walked (it's quite safe) around Havana talking to people, seeing some monuments, going to bars and such.
The real pain is money. Your cards will not work at all anywhere in Cuba due to the sanctions. No ATMs because of this. So you need to bring all the money you need. Many places will take USD or Euros, some things you need Cuban Pesos for and you'll want to find someone on the street to change it out with and haggle the rate. The official government exchanges give abysmal rates.
Cell service on your domestic plan ranges from non-existent or still stuck in the early 2000s where moderate usage will cost $1000s... But I was able to get a local tourist sim for $14 for a week and just didn't use my home cell data.
The Treasury can ask for receipts for 5 years after your trip but as far as I've ever heard they haven't asked anyone about it.

Sometimes you can get a really good trade in deal. Just pay it off immediately and it will be unlocked, then you'll usually get bill credits for 2 years. You'll have to stay with that carrier for 2 years if you want the full discount but every month is you saving off of the full retail price, so as long as you plan to stay a few months anyway you're still saving.