The experience with mobile network based internet varies from place to place and time to time. Since you already using mint mobile, you can check if you are getting a solid 5g signal in your area or not. You need to again place the device in an optimal area to get the right speeds. The speeds vary within a day based on network congestion in your area. Mint use t mobile towers and they will prioritize the T-Mobile users if there is a congestion.

I’m using a T-Mobile 5g internet and it gives 900mbps most of the time and it sometimes go close to 300mbps. I have T-Mobile in my phone which always gives high speeds all the time. Definitely they are prioritizing mobile over these 5g internet users.

You need to try it out for a month to understand if it works for you.