That is patently not true. The State Department already says they will not accept an amended bc that is filed after a year (or just ones that look funny, like some tend to), and adoptees have already been denied driver's licenses and/or passports since REAL ID started coming into effect. The government wants the original. Well, sorry, 44 states won't allow access. They have now stated they will accept an adoption decree, but I don't know of anyone that's tried that yet. (And you have to do special things to get it.)
I had no problems getting my passport (either time) with my BC. I was adopted between my 2nd and 3rd birthday. It is no different than my non-adopted sisters' birth certificates, doesn't list my birth mother, and lists my step-mother as my mother. My sister, however, had to go and get a short form because she tried to get her passport with her "original" (which isn't anything more than a memento for parents). [Edit: Although this might be because of how my birth state issues BCs to adoptees.] No one has their original birth certificate.
If this were ever an issue on renewal, I wouldn't see it as any more intrusive as the questions asked of USC children born overseas at the issue of their first passport.
The irony over the race issue with this is my birth mother had four children before me. They were all multi-racial, but only two of us have the potential for issues with this and it has absolutely nothing to do with our race. We were just the two who were adopted after my mother's death.
If there's anything to compare to the poll tax here it would be the cost to get a passport in the first place.
ETA: And we should wait to see the new rules when and if they are implemented. Until then, I am going to get worked up about speculation on what the new rules will be and what birth certificates will be accepted and what won't when I renew my passport.
Googling this, it seems that this has supposedly been an issue for people for 20+ years (yet always someone the poster knows or heard about). If this is the case, then this might actually be a step to SIMPLIFY the process for adoptees who run into problems (supposedly). I'd rather have the option to fill out the information to the best of my knowledge than to try to obtain my adoption records. But I think this has been used as a way to appeal for legislation that will allow adoptees to access pre-adoption records (or in the very least get people sympathetic the "cause"). Supposedly, adoptees have had problems getting passports for so long, then why are so many of us getting passports and even newer enhanced IDs/licences with no problem? Sorry, but I think this is about something totally different than having to answer questions before getting a passport.
There might be very valid arguments in favour of opening these records to adoptees, but this is not one of them. Believe me, I know how lucky I am to have my father tell me everything he knew about my birth mother and older half-siblings (all of the surviving I've talked to and almost all met in the past few years). I feel extremely fortunate to have that connection to my birth family, and I think that there has to be another way to handle birth information in the States. This isn't an argument in favour of that change though.