Why the heck would you use the phrase "Why the heck" in any circumstance other than to avoid censorship/algorithmic penality on a social media platform?

Well, one good reason is that a person who generally doesn't "swear" can then choose to use them very effectively when the situation warrants. If you always go to strongest words when mild ones will do, you're out of things to say when you need to make a stronger/more forceful point.

And there is nothing better to use for the headline than a minced oath if you explicitly don't want to swear? Make it make sense.

Perhaps instead of worrying about someone else's free choice to use certain words iver others, it would be wise of you to ask: why would you complain about forced speech patterns in the context of censorship but then be angry when someone uses their free speech differently then you would use it?

I say "heck" instead of "hell" all the time. I'm not religious, so the invented "heck" is more of a swearword.

Because being consistent helps prevent mistakes in circumstances where use of regular curse words is contraindicated. And why the fork should you care?

These things tend to get ingrained in you so you continue to use them even if you could technically use the words they replace.