[adrian_b]

This is exactly what I want in a smartphone, but the traditional smartphone vendors do not want to offer.

That means a smartphone that allows me to not carry a laptop, whenever the smartphone is adequate. A portable external display is lighter and easier to carry than a laptop, especially when compared with a laptop of the same screen size. A 17" portable display would add negligible weight to your backpack, but the same cannot be said about a 17" laptop. I also prefer to carry a compact ergonomic keyboard, instead of using the awkward laptop keyboards.

The only disadvantage of this smartphone is that it uses an old Qualcomm SoC, which predates the modern Armv9-A CPUs, i.e. it contains four 6-year old Cortex-A78 cores (and 4 little cores of negligible importance for performance).

Nevertheless, even a quadruple Cortex-A78 is faster than the fastest light notebooks of 10 years ago (which used Intel Skylake/Kaby Lake CPUs of the U series). Those notebooks were good enough for professional work then, and they remain acceptable even today, so such a smartphone should be also adequate for things like reading and editing documents or program sources, browsing the Internet or compiling software projects of moderate size (or incremental compiling of big software projects).

The same Qualcomm SoC used in this phone is also the best chip that is available today for small single-board computers, e.g. of the Raspberry Pi credit card size, and there a few companies that offer such SBCs (which have much higher performance than any Raspberry Pi; examples are Radxa Dragon Q6A and the Particle Tachyon 5G SBC). This means that Linux support for it is good and improving.