Long covid is definitely a thing and it is totally not like a common cold.
I think it is similar to long term effects of some more serious viral infections, like flu.
It seems to be a combination of damage and/or stress to the nervous system and immune system going paranoid on you.
Personally I've had tiredness, brain fog, inflammation and increased bronchial secretion for about 3 months, now after 4 months I'm ALMOST back to normal, but not 100%. I've never had anything in my life that would last that long, but then again I'm generally healthy and fit.
Jabs had nothing to do with it, I've had two, last one was more than 4 months before the actual infection. First jab was very mild symptoms, second one sucked for 3 days, then back to normal.