SO vs THAT (adverbs)
What is the difference between so and that when used as advers as in following sentences:

not so much / not that much
I'm not that stupid / I'm not so stupid

Thank you very much indeed

Regards

Question

SO vs THAT (adverbs)
What is the difference between so and that when used as advers as in following sentences:

not so much / not that much
I'm not that stupid / I'm not so stupid

Thank you very much indeed

Regards

Answer

'that' refers to a quantity that has been stated or presented, i.e. someone is pouring wine in a glass for you, and they've poured too much, so you say 'not that much'.
'not so much' would be said before they've started pouring.
however, in practice, the two are used pretty much interchangeably.