Second hand mini pc's are a good option. Half the price of a pi 5 + sd + power and you often get them with 16gb ram, a decent ssd, etc.
If you need GPIO then many of the rockchip boards are still fairly affordable and easily had.
You know what I do want though? An actual damn HDMI port! HDMI cables are everywhere, wherever I am I have unlimited options to connect an HDMI device to some kind of screen. But micro HDMI? The literal only thing in my life that uses it is the Raspberry Pi 4 and 5. There have been plenty of times where I've reached for a Pi 3b instead of a 4 or 5 just because I didn't have a micro HDMI cable.
I do not understand what has gone through their head. How could anyone look at the use case for a Raspberry Pi and decide that two micro HDMI ports is a better choice than one HDMI port? I don't understand it. Like you, my experience with the Pi is that they mostly just sit there, headless, so the only reason I need display output is that it's useful during setup (because they don't have a proper serial console port).
I can't set up a Pi 4 or 5 without going hunting for that micro HDMI cable I bought specifically for that purpose and never use for anything else. I can set up a Pi 3b anywhere, at any time.
Being able to run two sides of an advertising board, or two control panel screens on a big hunk of metal doing fabrication things in a factory was more important to Raspberry Pi as a business apparently.
Why he heck they didn't just go with 1x normal hdmi and 1x usb-c +DP for the Pi 5 is a mystery, perhaps the SOC doesn't support it or something.
Have fun reading 40 answers about how discarded Lenovos from 2017 are cheaper and stay idle at 5W. It springs to 3x the power usage of a pi if they do anything with it but who cares about performance per Watt?
Radxa Rock 5C and Orange Pi 5
I would do research on them because they are a similar form factor and usually cheaper for more memory… the software will be different.