435 is an arbitrary number and represents where we were when we stopped adding Congressional reps in the 1930s. Prior to then, we added reps every 10 years after the census. It’s a little known remnant of that era that should be corrected. There’s no written legal doctrine locking us to 435.
Noth will change until Term Limits is imposed. Polls consistently show the vast majority supports Term Limits. But Congress simply won’t do it.
Temr Limits will only happen via Article V. After that, other great amendments can be passed. But not until then.
Term limits as an output of an Article V action will sail through the 38 state ratification process.