There was a time not very long ago when alt coins went way up and suddenly GPU mining was super profitable again. Then apparently everyone on the planet bought up all the video cards and started mining. With a single card, mostly what you will be doing is paying the electric company to buy a small amount of cryptos. But doing that has paid off tremendously well for me in the long term. There was a time a number of years ago when I had 5 GPU's mining LTC and I was kind of stoked to be getting $2 a day with those 5 cards, even though I was paying more than that for the electricity. Since I have kept more of my cryptos than I have sold over the years, that mining has retroactively been worth much, much more than that. I suppose the ultimate value in fiat will be determined when I cash out, but from my humble beginnings (those 5 video cards) I have over the years accumulated a number of asic miners, and newer GPU's. I have 7 GPU's now and I earn around $100 a day between the asics and the GPU's, but the coins I have accumulated and hodled and traded with on exchanges are worth like 100k.
The point is really that you don't know what the future holds. And the decisions you make as to what to mine, and how long to hold it will determine how much money you make per day mining more than the point in time calculations (unless you just sell everything right away of course). If you sell everything right away it is hardly worth it though. As I say, you will just be paying the electric company to acquire small quantities of cryptos in that case. But if you are mining something and only making $1 a day now, if it goes up 5 times in value in the future and you never sold it, then you will actually have been making $5 a day retroactively.
The real crypto gravy train has already left the station. But there is still time I think to make some decent profit if you look at it like a long term investment and not just a matter of how much can I make today.
I wish i had your foresight, I mine a ton of cryptos in my day neevr held much , always sold on the latest pump , great post