The disinformation is flowing already in some cases.
But the posters citing (vacuum) tube saturation are correct. Combined with proper technique e.g. finger vibrato, long sustains with a ‘hot’ amp are hardly a chore.
Santana, like many iconic guitarists, is a bit of a purist therefore his emphasis is on the amplifier rather than a load of effects. As someone once pointed out, if you want tube saturation and an all-analog sound, why are you running your signal through a solid-state germanium transistor-based pedal?
Mesa/Boogie is a well-known name...the first Boogies were hot-rodded Fender Princetons and one of the early adopters was...Carlos Santana, who also used subsequent original-design Boogie models.
There there is the Dumble Overdrive, a Holy Grail-type of amplifier made by hand by its eponymous inventor and only when he feels like it. No two alike etc. Tens of thousands of dollars.
And a 10+ year waiting list to get one built. And if you piss off Alexander Dumble by asking him if he's started building your amp yet, he'll send you back to the bottom of the list.
Anyways, it couldn't have been a Dumble on this 1976 track. Santana didn't get his until after he saw Stevie Ray Vaughan playing through one.