Or, if state level actors are looking at your data they are buying from companies, the appearance of intentionally corrupted data could invite more scrutiny.
If state-level actors are looking into your data with any amount of individual scrutiny you are already fucked, this is a ridiculous reason to not use ad nauseum.
Imagine being in China where they tend to watch you and make profiles on you. Then suddenly the profile of who you are goes completely random. Is it possible this gets the attention of state-level actors where you had none before?
Poisoned data would be useful in the fight but yeah, "garbage data looks like someone else's" is certainly superior to "garbage data looks like it's yours".
I guess in the long term it depends how good the profile builders get at anomaly detection, and at which scale we're talking about.
While many states in the US have laws against it now, for awhile there companies were basing if they would hire you based on your social media profile. Having no profile at all may exclude you from getting a job. Or, when I went to get credit for my the first time in my later 30's. I had always been a cash buyer before then, and proof of my existence beyond my ID was sparse, the guy on the other end of the line was like "Did you even exist before yesterday?"