Yes, I am assuming that all mining is done with GPUs for ETH/ETC/ZEC/XMR and some others. I'm only including coins which are currently profitable to mine on GPUs, which I take as an indication that those algorithms have seen little/no efficient ASIC implementation yet. I'm thus not including bitcoin, since GPUs are little more than space heaters mining bitcoin; and I'm not including e.g. lbry and litecoin and some others because I don't know enough about the ASICification of those.

It's possible, though, as you suggest, that there are some folks running ASICs or improved hashing algorithms at a small scale, small enough not to overwhelm profitability of GPU mining but large enough to muddy calculations which assume that all mining is being done on GPUs.

GP states they are referring to "... the major GPU-minable coins ... ".

I interpreted that as "possible to mine on GPUs", not "profitable to mine", but I guess I misunderstood that.