Can public political criticism of my alma mater result in my BA being revoked 35 years later?
I've been working in Academia for the past ten years. The only cases of degree revocation that I am aware of were due to severe cases of academic misconduct such as plagiarism, fraud, or large-scale cheating. The rationale is that gross academic misconduct invalidates the achievement the degree should certify.
Revocations on grounds of expression of (political) disagreement with the issuing institution are unheard of in rule-of-law democracies. I've never heard of such a case, although it would certainly have become very well-known.