The problem is that are very few cpu's, chipsets or SOC's that can run blob free.
https://www.fsf.org/resources/hw/single-board-computers
H-Node is a new resource for finding hardware supported by fully-free distributions of GNU/Linux.
https://h-node.org/hardware/catalogue/en
https://h-node.org/notebooks/catalogue/en
It lists hardware supported by open source hardware but hardly any are blob free.