I worry less about the data overage and more about how fast the life of the battery would deplete, unless you have your phone plugged in while doing hotspot, I suppose.
For our home internet, we used to have the lowest level from Spectrum (cable company) and it was overall acceptable but nothing stellar. We recently switched to T-Mobile home internet which essentially really is using cell infrastructure to provide internet service. It is, in a way, hotspotting but not from a phone, but rather a cellular to wifi gateway/modem.
Whoa! I was blown away by the speed. It is a LOT faster than our Spectrum internet, cheaper by like $20 to $30/month, and much more reliable. We have been very pleased.
Before we switched over, we called up Spectrum to see if they were willing to lower the price of their service. They weren't. Too bad. We went with T-Mobile and trialled them (we had like 30 days free or something like that). After using it for a little over a week and being blown away by it, we called up Spectrum to say we're cancelling. THAT'S when they were trying to keep us by saying they'll reduce their monthly service charge, etc. etc. Too bad, so sad. We're not returning. LOL.
I'm really amazed how fast the T-Mobile 5G home internet is. It's must faster than we need for both the upload and download speeds.
(Our home which was built in the 90s has built-in telephone line and cable (just like any house in the US back in the 90s). Do houses these days come with landline and cable? We use neither. LOL )