Open source FPGA toolchains begin to appear, mostly on the low-end for now. And because all FPGA vendors are doing such a terrible job for tooling, Yosys and friends are likely the future.

Very true; Lattice Semi’s ECP5 is a fairly decent FPGA with very mature support from Yosys/nextpnr/trellis.

Xilinx’ Artix-7/Kintex-7 are much more powerful FPGAs and the support for those is getting to be pretty good (DDR3 support is steadily maturing)

It would be nice to see a vendor actually officially supporting these efforts. Maybe one day.

(Not to mention various open source FPGAs - actual chips - being developped)

Treat them as purely hardware vendors and go open source tooling. The tooling is infinitely superior from a ux point of view. There are still quite a bit of missing features but it is getting there.

We've heard positive opinions of the Xilinx boards and tooling. At least, not having everything about the HLS tooling either changed or syntax deprecated every three months.

But Xilinx has the absolute worst SERDES interface. Microsemi's Polarfire was way easier to get 10G ethernet up and running on (hours vs weeks).