The advantage of ARM in laptops are clear - the battery life/performance/heat tradeoff is better. It’s also clear for server farms.
But if I’m just running Linux on a desktop anyway, why would I care about ARM vs x86 unless I’m targeting my builds for other ARM computers.
On the other hand, for a very cheap, secure and fanless (i.e. reliable and silent) network appliance, like a firewall/router/NAT/Web server/e-mail server etc., a small ARM-based computer, e.g. one with RK3588, may be the best choice. (but not all ARM CPUs are documented well enough to make them more trustworthy that the Intel/AMD CPUs)
If your insecure personal computer is shielded from the public Internet by a secure firewall, you need not worry that its remote management features, which are supposed to be disabled, can in fact be activated without your knowledge.
And that would depend on the processor more than anything else. E.g. raspberry pis consume more power on idle than some of these x86 boxes which are more powerful (but more expensive)
The "uncompromised security" line suggests that the product is targeted at this group. The Intel CPU shows that it's actually aimed at people "just running Linux on a desktop anyway".