We know the Taliban are making rather quick headway to take over territory since the US withdrawal.  We also know the Afghanistan army hasn't been extremely effective and isn't very well equipped, notably in air support capability.

It's not necessarily a question of courage either - Afghan military casualties have been high in the last few years, this war has been taking a large toll on their troops.  But they have received at least some fairly good Western equipment, I assume.

It seems odd, though not unprecedented, to see rebels making such quick headway.  South Vietnam in 1975 might come to mind, but that was a conventional invasion by North Vietnam.

We also know many locals, not just people associated with Western forces in the past, indicate apprehension at the return of the Taliban.  They weren't very pleasant the last time they held power, 20 years ago.  However, the Taliban were also relatively well-accepted initially, in 1994, as they were displacing Afghan warlords who had made life miserable for civilians for years.  (Well-accepted may be stretching it, but they encountered little opposition).

Finally, we know that the Afghanistan government has, at least in the past, suffered from a lack of legitimacy.  Some of the past elections were rigged and corruption seems endemic.

**So, do we know what proportion of Afghans back the Taliban's return to power?  Are they, in Mao's words, fish swimming amongst a sea of support by the population as a whole?  Are they accepted with resignation, in the hope that peace comes back?  Or are the majority of people opposed to their return?**

(Yes, I fully realize how incongruous it is to ask about anything resembling an opinion poll in Afghanistan right now.  It's also a challenge to get reliable opinions from a representative sample of the population, not just the people in areas still under government control.  I'd be interested in any credible press coverage).

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Addendum on acceptance.

- I disagree with the rather wild claims of high Taliban popularity made when this answer was written.  I suspect it's less *support for* the Taliban than it is *lack of support for Ghani's government*.  And a desperate wish from large parts of the population to see the fighting end and little benefit from development for the rural masses.  **In accepting it, and though the answer makes no real claim in that direction, I don't believe that the Taliban will be an improvement for Afghans.**

- The rest of the answer is quite informative, which would on its own motivate accepting it.  Yes, even if some of it seems somewhat opinionated and though it talks more about the *how* and *why* than trying to answer the question of popularity numerically.

- The other answers are very short, claiming very high level of anti-Taliban commitment into 2019/2020, citing well-known polls.  Or citing anti-Taliban sources.  Looking at the last 6 weeks' events, the polls seem wrong, at least in term of actual anti-Taliban commitment and capability.  These answers are telling us what we like to hear - which makes them popular - but probably nowhere near the actual situation.