I just looked through the United rules for next year. Not really a surprise as earned points had already moved to dollar-based. But it does look like it will be harder for me to gain the same status next year as I did this year. (Which was actually already a bit of a step down from the past few years.)
It does make sense from the airline's point of view. They care about your money, not how many miles you fly with them. In fact, they probably would prefer you flew fewer miles (which cost them) and spent more money.
Also, cynically speaking, it's often a lot easier for employees to spend more money on flights than it is to take more flights and thereby get more butt-in-seat miles. There have been qualifying dollars for a while but they weren't that hard to hit and ways to get waivers. Now there's a direct incentive to spend a bit more on a ticket if you're near an award level.
I've got Ambassador at Marriott, so I get UA Silver free (an hertz 5-star diamond presidents circle elite or something similarly foolishly named), its not a bad combo, it gets me in the front of the airplane, and saves me a baggages fee.
I'm the flip. I'm now Gold on United which gets me Gold on Marriott. (I stay in Marriott a fair bit but not enough for Gold and that doesn't give you Lounge access any longer anyway.) I'm assuming the relationship is still in place next year though I haven't checked.
A bunch of programs went a bit cross-status nuts a few years back but those seem to be slowly going away or getting watered down.
It does make sense from the airline's point of view. They care about your money, not how many miles you fly with them. In fact, they probably would prefer you flew fewer miles (which cost them) and spent more money.
Also, cynically speaking, it's often a lot easier for employees to spend more money on flights than it is to take more flights and thereby get more butt-in-seat miles. There have been qualifying dollars for a while but they weren't that hard to hit and ways to get waivers. Now there's a direct incentive to spend a bit more on a ticket if you're near an award level.