[k0stas]

The largest FPGAs were reticle-busters when I used to work on them. Today I think the largest FPGAs use chiplet-style integration. Even with the inefficiency of an FPGA, many smaller chip designs can still fit on the largest FPGA.

Also, there are prototyping boards specifically built for emulation that integrate multiple FPGAs, although this does introduces a partitioning problem that has to be solved either manually or via dedicated emulator software.