Isn't Pixel 10 the first one with fully supported desktop mode?

I remember I was very confused when buying a Pixel 7 to replace my (then 3 year old) Huawei P30 Pro, and the inferior camera + lack of desktop mode made it feel like a net downgrade.

According to Google's help site, no Pixel has a desktop mode (like you can find at Motorola, Samsung and others).

The latest Pixel models have DisplayPort, but their operating system only provides screen mirroring or app window mirroring on an external monitor. Unlike Pixel, the phones with a true desktop mode can display multiple windows on the monitor, and presumably they can have a selectable resolution for the monitor. I assume that for screen mirroring the monitor is used at the same resolution as the phone screen, i.e. either 1080 lines or only slightly more.

Moreover, while the help site states that DisplayPort exists in Pixel 8 and newer, Google does not bother to advertise the existence of this feature in its online shop, where there is no mention about this in the phone specifications.

I use it on my Pixel 8 Pro too It's a toggle in Developer options, Local Desktop.