I agree, although I have seen some phenomenally large dandelions - they were growing from the basal rosette, but the individual leaves were… I dunno… nearly a metre long; the flower stalk even longer - usually specimens like this are found as established plants (several years old) growing on the remains of a compost heap or some such - so they have a very deep, fertile root run.
Another contender for the ‘mistaken for giant dandelions’ trophy would be goatsbeard - a related plant with not-very-similar leaves, but very large, tall flowerheads that produce very much larger and more robust ‘clocks’ (seed heads).