But beside that (whch surely is the main reason), there is also a great difference between pozzolanic and portland, nowadays (and since several years) pozzolanic cement (for whatever reasons[1]) came out of use and anything today (and since several years) is portland.

I have worked with both in massive structures (mainly bridge foundations and tunnel lining) and the differences between the two is staggering, in practice portland cement based concrete is very good (compression resistance) already at 3 or 7 days, just fine at 28 days, but tops around the 60-90 days.

Pozzolanic cement based concrete is barely reaching specs at 28 days, but continues to mature (increasing resistance) for years to follow, expecially in massive layers and in humid environments.

If you prefere Portland is a better cememt because it is fast, but - given time - pozzolanic is way "stronger".

In tunnels (which have all the best requisites for concrete to mature correctly) we had at the time (some 30-40 years ago) specs of 250 Kg/cm2 cubic resistance (at 28 days), we used pozzolanic cement for the lower arch and portland for the vault, while both reached specs, after 2-3 years we made some tests and the vault (portland) reached 300, in some cases 350, the lower arch was never below 450, in some cases 500 and even 600.

[1] essentially because it cures faster, allows thinner layers/slabs and for anything where formwork is involved this makes a huge difference