If you're trying to buy a new T-Bill, you're impacted in that new debt can't be issued so new T-Bills can't be issued freely. For existing debt holders? Yawn.

If you're trying to buy a new T-Bill, you're impacted in that new debt can't be issued so new T-Bills can't be issued freely. For existing debt holders? Yawn. US Tax is revenue is ~ $450 billion/month. US debt service is about ~$60 billion/month. What's impacted is new spending.