So "příliš" (too much) can be used alone, when is followed by a verb, and becomes "příliš mnoho" (too much) when combined with a noun?
Why is 'you are talking too much' wrong?
You speak a lot - what's wrong with it?
It corresponds to "Hodně mluvíte." Both languages distinguish between large quantities and excessive quantities.
"a lot" doesn't have to be too much...
You have a lot of food on your plate. (that's a good thing)
You have too much food on your plate. (not so good) --- feel the difference?