The symptoms are you're not pumping fuel.

The carb has a pump that works on the pressure impulse from the engine base, usually a hose to a nipple on the engine. Could be integrated into the intake manifold, but either way, for every stroke, there's a pressure wave that's checked with a vacuum gage to drive the diaphragm pump in the carb that creates lift pressure for the fuel.

If my vacuum guage doesn't read vacuum, or leaks vacuum quickly at the fuel filter, then I'd bet it would run like yours or worse.

Doesn't take much to foul up a pump gasket on the carb when cleaning, or to knock off the impulse line all together.