I definitely see what you mean, but at the same time I think there's a whole lotta room for creativity depending on your knowledge/understanding. Of course you can't get at the inner layers of PCBs and modifying silicon chips are impossible, but there's still plenty of room around those constraints.
Look at this project that repurposes the FPGA in some Cisco modem: https://tomverbeure.github.io/2021/05/16/Pixel-Purse-LED-Cube.html
The Xilinx Zynq chips on obsolete bitcoin miner control boards are also completely reprogrammable https://github.com/xjtuecho/EBAZ4205
And, "pic related," why not design your own PCB or even silicon? Hardware development is more accessible than ever now, with things like that skywater foundry pdk