So according to 7zip and unixbench benchmarks RPI 4 with out of order CPU on 1,5GHz is on par with Odroid C4 with in order CPU on 2GHz. And the price you'll pay to get one will be closer to 70$ in EU including shipment costs or reseller fees.
There is only one other cheap computer with ARMv8.2-A: Khadas VIM3L (a little more expensive, less DRAM, WiFi included, another variant of the same processor, no USB hub but PCI-E on an expansion connector).
C4 comes with a large heatsink. Rpi4 doesn't despite the much higher power consumption, forcing you to add one.
My conclusion: The RPI4 is an unreliable, poorly engineered toy (like every other RPI in the past). The C4 is rugged and a good choice to base projects on, like every Odroid has been to date.
My experience is the opposite. The raspberry pi ecosystem is low quality and full of quirks and annoyances.
All the alternatives I have used (mostly sunxi-based) have been a much smoother experience.
The ARM boards make sense only if you have power and size restrictions.
Power and Size restriction can be a bigger deal than you've made it sound, though. I can fit ten Pis in a carry-on without concern if needed, and I have needed to do so in the past. For noise reduction, fanless is better than muffling a fan, though one does need to make sure the heat sink is big enough.
This is great. If you absolutely do not care about power efficiency, physical size, noise or reliability.
They aren't even comparable. And even if you claim to care about raw performance, I'd like to see how well that i3 does in a direct benchmark. It might not turn out the way you think it is.