No, this doesn't permanently alter the DNA sequence.
But, it is like commenting out regions in code. You are factually right, in that there is no editing of the DNA sequence i.e. no mutations. But this phenomenon exerts a similar end effect.
Not "end", exactly - at least, not if you look past N generations.
The question is, how many generations does it take for this to wear off? Or is it "good until cancelled"?
Doesn't matter. It's the "reflections on trusting trust" kind of thing - we, our parents, grandparents, etc. form a chain; some runtime modifications to replication mechanism could propagate forward indefinitely, without changing the DNA in the process.
Nice insight. To save a few clicks to those remembering this classic (or reading for the first time!):