It is impossible that the laws of physics have not changed with time.
At least, for the reality I seem to live in.
The question should not be whether or not things change, but how to measure and quantify it.
“Have We Got The Big Bang All Wrong?” by Will Lockett:
The CMB derived measurement assumes that physics was the same in the very early universe as it is today. This assumption has been questioned before and we don’t yet know if it is correct. But if physics has changed with time then this discrepancy in the CMB could* be the fingerprint of it.
Not to be too overdramatic but this would rewrite physics. Because the idea that physics doesn’t change with time or location is key to the framework that physics is based on. Discovering that physics has changed with time is the equivalent of pulling a Jenga block from the bottom of the tower. The whole thing could come crashing down.
*Key word: could.