That GM definitely has some stories

Those are, in fact, perfectly sensible guidelines.

So professor burp is still on the table?

Those are very reasonable and wide guidelines.

So this is my character. Her name is Armpits Esquire and she’s three halfling paladin brothers from a dead order in a trenchcoat. Because of their stacking auras, they are nearly- no, you can continue loading, it gets worse.”

So...Doctor Farts can do 1500 damage per turn by level 3.

Nah. Doctor Fart can do 1499 damage per turn by level 4.

The second one sort of depends on the player. I've had a few players that have made absolutely ridiculous characters but played them very well and it was a good experience. The first one is a strong no. I've never seen anyone who does a broken meta build do anything beyond ruin everyone's time and complain (or quit) if the DM reins them in at all.

In half the campaigns, the Doctor Farts PC ends up being the MVP because they weren't minmaxed and as a result have much more utility.

Nurse Practitioner Patricia P. Poopu is fine too I bet.

The dookomancer Dia Rhea.

Thinking about my 3.5 gestalted murder hobo days

Character called Mr. Farts that deals 1500 damage per turn by fart 3.

Special skill: bag of holding with infinite cabbage and bean stew supply.

I was once in a game where the GM allowed his buddy to be a build like that, but in a nifty "hidden origins" way, where the PC slowly realises their own immense power, but is super clumsy with it, so they're an active danger to the party but you also can't just leave them at an inn because they can potentially destroy the world if they have a nightmare... Then he got turned into the campaign's secret big bad that was only revealed at the very end. THAT worked out well. Turned out he could control his powers and just used us to get rid of his also evil archnemesis of his before attacking the party.

That sounds like an epic DM/experience!

Bag of farting

Doctor Farts: "I cast Stinking Cloud, again." Party: *sigh*

Prison wallet of holding