Depends on the country.
In the UK, the above is completely bogus.
I know this because I was involved in two projects (for separate companies) where my job was to facilitate the migration of
traffic from the analogue bands to the digital spectrum. I wrote software that would allow the radio experts to predict what
would happen to traffic coverage if they increased/reduced power on specific sites, if they went from monopole to three-sector,
or if they took a band from analogue and gave it to the digital network, or if they increased site resolution.
We also did simulations to determine finer grained traffic analysis than the data provided and (in both cases) we identified
coverage holes (that turned out to be real) in central London, United Kingdom.
And that was in 1994 (for the UK) and 1996 (for the rest of the world, with the primary focus the US)
As far as the main carriers were concerned analogue was on the way out in 1994, expecting to be completely replaced a few years later.
Its possible they kept the networks running longer than anticipated (I don't know, I did other things after this), but the
idea that the analouge bands were not being migrated to digital in this time frame is totally incorrect, false and misleading.
And in the UK, we've been digital for at least 10 years. We had our 3G auction in 2001.