I have a sizeable tax lien against me which has been considered uncollectable, will this prevent me from obtaining a US passport?

No, you should be able to get the passport.

Presently "noncollectable" does not relieve you of the tax liability. The time limit for the collection of the dues also freezes. That is IRS has 10 years plus freeze period to collect your dues.

I have substantial tax liens deem uncollectable but not over 10 years, could I get a passport?