It's easy to just buy a SIM with reasonable amounts of data on it, and recharge as you go. All options are very reasonably priced compared to US. Might be true that you can get cheaper yet with a short-term monthly plan there, up to you if it's worth the hassle for however long your trip is.

I don't know what brands are common at the moment there, I used "Tre" service on my last 3-month tour around southern Europe in 2017 and had zero problems.

Definitely DON'T do a travel plan with your US-based carrier, that is the most expensive possible option. Swapping SIMs is trivial. The hardest part will be not losing your tiny original SIM.