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.
