You have already seen that in affirmative sentences with depuis (= I have done this since/for + [date/duration]), you must use Le Présent (Indicatif) in French, unlike the English Present Perfect.
See lesson Using the present tense (Le Présent) - and not the compound past (Le Passé Composé) - in sentences with "depuis" (since/for) in French (French Prepositions of Time)
But things change when it comes to negative statements (ne...pas) with depuis.
Indeed, in such cases, you will actually use Le Passé Composé (Indicatif) in French.
Negative sentences with "depuis" in French
Look at these examples:
Here we use Le Passé Composé (Indicatif) because the use of the negation ne ... pas insists on the fact that the action wasn't done during the entirety of that past period, hence Le Passé Composé.
Using Le Présent (Indicatif) here sounds like you're talking about a current action with a past date, which is non-sensical
-> You don't drink alcohol for 5 years.
To emphasise that a (recurring) action in the past has now stopped happening with depuis, you can also use Le Présent (Indicatif) with ne ... plus (not any more) instead of ne ... pas. Here ne...plus focuses on the change between the past situation and the new current one, which it highlights, hence Le Présent.
Special case of depuis longtemps = not long vs not in a long time
Ne ... plus + Le Présent (Indicatif) + depuis longtemps
= not for a long time / not in ages
-> It's over and done in the past
-> It started a short while ago, and is still ongoing
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