I won't speak for the OP but for me: Status
I book uneconomic flights all the time because the net-net benefits are worth it. I think that's the entire point of loyalty programs, to capture more spend than you would be able to just based on price competition alone. This is particularly acute on some INTL routes where I could absolutely fly better product but want to concentrate my spend with UA/AA for the sake of the other 119 flights I'll have that calendar year.
Thats the gist of my point, really - I would always book UA even if more expensive. In fact, on every trip there has always been a cheaper option, but I chose to consolidate on UA because it was undoubtedly worth it for the collective benefits of the GS program . They would capture 99% of my business and leisure spend.
These days, though, with some of the key program changes like the one companion segment rule, that percentage can drop as I use other *A carriers with cheaper business fares.
I won’t abandon UA and really like the airline - but if you are a traveler that is not focused on upgrades, you could hit the minimum dollar spend on UA for GS and shop the rest. I’m sure that’s not what UA are striving for - but a reality now of a program that has fewer benefits above 1K in the eyes of some travelers.