You are so very correct,

but
there does exist a very real and not so very small
linux power-user market segment.

And we might rephrase your observations:
(google also "CODE 53")

“Did you sell it to us or is this just a trick to get your hands in my pockets ?”
With Ubuntu I have some serious doubts.
They have an agenda that orbits around a very 'top-down' attitude.

I just checked Handaxe's comment about the email client,
(after deleting it months ago I reinstalled it to see,
now - ver 6 on OTA-9 on BQ's E5 )
and DEKKO remains a 25MB! steaming pile of rancid swine tripe filler.
23 MB of that is a copy and pasted binary,
managed by a swarm of qml statements
(you can, redeemingly, see the source code on github)
claws-mail (apt-get installed) is only 2631276 bytes. go figure

And with the way it is being developed Dekko will remain such
until hell itself freezes over permanently.
The latest version fixes dozens of lipstick issues and
leaves the configuration multi-fail abortion in purgatory.
This app should be a textbook example of top-down fail.
How they keep the Dekko name is a mystery.
Dekkosecure.com looks to be selling email clients as well
and I would anticipate some friction there if they are not joined at the hip.

I'm constantly bugged by people's use of the word "multitasking" to refer to things it really bears no relationship with.

I'd say pretty much all modern devices that are usable at all support multitasking.

Proof; ssh to your device or open a console and type "ps aux"
What do you see?

If the device UI & launcher supports only some braindead notion of interaction model, well do you have to live with it, huh?

@juiceme, multitasking means literally, "performing several tasks simultaneously". A device that allows me to do that can be said to "support multitasking". A device that does not, can't. Why should I, as a user, care if the device itself can run mutiple processes if it does not allow me to do that?

Why should you care to use a device which by itself can perform multiple tasks but is artifically limiting your ability to use it as you please?

I don't