We received the same email from Starlink last night. The email sent to us said (in bold print) “Based on your data usage over the last six months, this policy will have no impact on your service.”
We have a fixed Residential Starlink system at home, and an RV Starlink system that we use in our motorhome. The Starlink email said, Residential Starlink systems will get “priority service”, on a month-to-month basis, until one terabyte of data is consumed, then it will be de-prioritized. They don’t say exactly how much they’ll deprioritize the data rate, but as a possible frame of reference, our RV Starlink system is always deprioritized, and we’ve never had a problem streaming HD shows, or getting high speed internet service.