What does HackerNews think of apio?

I think there are a lot of major developments in the last 20 years, although I'm not active in the field. Symbiflow is largely a distribution of yosys, a bunch of other IceStorm projects, and nextpnr (is that part of IceStorm?), in the same sense that Debian is a distribution of Linux. Another one, but I think limited to Lattice FPGAs, is https://github.com/FPGAwars/apio.

I think the biggest development, though, is that there's enormously more off-the-shelf Verilog and VHDL, not just on OpenCores like 20 years ago, but also on GitLab, GitHub, and so on. Easy examples are CPUs like James Beckman's J1A, the VexRiscv design used in Bunnie's Precursor: https://github.com/SpinalHDL/VexRiscv (as little as 504 Artix-7 LUTs and 505 flip-flops), and Google's OpenTitan.

But from my POV the more interesting reason for using an FPGA is for things that aren't CPUs. For example, the SUMP logic analyzer and its progeny OLS https://sigrok.org/wiki/Openbench_Logic_Sniffer (32 channels at 200MHz), although I think both of these require the proprietary vendor tools to synthesize. I'm gonna go out on a limb here and guess that reliably buffering up data at 6.4 gigabits per second is not a thing that any CPU can do, even one that isn't a softcore; CPUs that run at speeds high enough to potentially do it invariably depend on cache hierarchies that monkeywrench your timing predictability.

As I said, though, I'm not active in the field, so all I know is hearsay.

if you're more comfortable with the CLI, you should take a look at the apio project (https://github.com/FPGAwars/apio). It neatly bundles all the required tools. Regarding HDLs, I'm still learning so can't offer any good advice on that.