Why does the debt ceiling even matter? Seriously...

Can someone kindly explain why -- from a pragmatic standpoint -- Congress even oretends to care about their "debt ceiling"?

I mean, it's not like they heed any other rules or restrictions they don't want to obey. Like the friggin' Constitution, for starters.

Why is the debt ceiling even an issue now, then, when it's apparently self-imposed, they go ahead and raise it every time anyhow, and they could just ignore it as they do voters' concerns/sweep it under the rug as they do their many scandals/vote it higher as they do their own salaries?

Is all this drama just a "tell" that Congress's real constituents all work on Wall Street and at 20th & Constitution?