The projects in question include things like a 48 port gigabit Ethernet switch with packet datapath in the FPGA, and dual 10/25G SFP28 uplinks. You're not doing that on a MCU. Also higher end oscilloscope work (e.g. 10 Gsps 12-bit JESD204B)

But a STM32 is more than sufficient for the management interface on both.