This was part of the reason I sold my XLR and purchased an XTS: More built-in convenience features.
I enjoy downloading directions into CUE from my iPad. It's convenient to say the name of an artist and have their music start playing. I like to be able to remotely start the car, (and have warm seats) from my office before leaving on a cold evening. The reconfigurable dash displays and multiple HUD info options are a nice touch. CUE is fine; --not perfect, but nowhere near as bad as many would lead you to believe.
While some upgrades were made to the XLR during it's production, it's showing its age technically. Visually, it's stunning. After seven years of satisfying ownership, it was time for me to move on, and I haven't regretted the decision at all.
While not impossible to upgrade the infotainment system, it is expensive, and very limited. Spare parts availability can be troublesome. Used, driver's side headlights in good condition are difficult to find; new ones are not available in the supply system.
For many, having the latest and greatest techno-features is not important; it all comes down to personal tastes and their lifestyle situation. It's nice to have options, --especially where Cadillacs are concerned. I'll always have a soft spot for the XLR, just not soft enough to want to own one again. I greatly enjoy (learning) and helping XLR owners whenever possible though.