This is a ridiculous statement that feels in my opinion very much in line with the recommendation to phone AS to ask for an upfare.

Their marketing material is not stated correctly and their marketing is deceptive. Any reasonable person doing their due diligence would still fall in that trap. This is why OP needs to go to DOT, get a resolution, and update us about the resolution.

Passengers should not have to guess in between the lines and play the roulette. How does a 'regular' customer flying Alaska is supposed to know that:
- Qatar Airways considers certain/all eonomy fare classes as 'Saver' when buying a ticket on the Alaska Airlines website
- A fare advertised as 'Main' on the Alaska Airlines website is not 'Main' (ie in a column that is neither titled "Saver", "Basic" or the more generic 'economy')
- When Alaska distinguishes Main as meaning "Economy" and "Saver" as meaning "Basic Economy"
- Alaska verbiage about anything that is not Saver should earn 100% of miles is in fact not supposed to be believed

Please educate us.
Cause, yes this is not crystal clear. And yes, there is ground for bewilderement.
In fact, in my book there is ground for mileage-compensation due to misleading advertising, and hopefully some DOT fines as well. Passengers should not have to spend time and energy complaining and emailing the DOT because Alaska can't write two sentences correctly on its website / and CSR are not empowered to do the right thing when the ethical course of action is obvious.