Adults also know that not raising a credit limit on a credit card is not the same thing as defaulting.
Other things adults know.
Without seriously restructuring your budget, it doesn't matter if you continue to pay the bills by increasing debt limits, you'll never get out of crippling debt and at some point you will reach bankruptcy.
Telling the family that we either restructure, or we'll force the issue because the limit is reached and won't be raised without serious changes... isn't "defaulting"...
And lastly:
The majority of the nation agrees with the adults.
If the debt ceiling isn't raised we either default on our debt or we don't fund any of the discretionary budget plus we don't fully pay for Medicaid, Medicare, Social Security and other mandatory spending. Pretending otherwise is stupid and dishonest.
At least the "default won't be so bad" people, while proponents of economic quackery, aren't telling objective lies.