I read that post that you're referring to. The problem is that you are either denying or not acknowledging the lost of opportunity. Mining is a hedge against a coin failing. Essentially you can say that can sell the equipment (well GPUs anyway) for nearly purchase price in the event of a coin failing. On the contrarian position - somebody who buys the coin doesn't have to sit there everyday to make sure stupid Win 10 update hasn't taken a miner offline or that the pool you're mining at is skimming of the top or even worse running away with your crypto. The person who bought it can spend the time saved earning more money to pay for the gamble or has the chance to exit quickly if they need to.
Once you have coins in hand you know exactly what your break even point is - the price at which you bought in at plus exchange fees. People who bought ETH last year at $300 should have sensibly sold some (if not all) at $1200 to $1500. Once simple click would have resulted in 5x fiat profit, and should they like - they could always rebuy the ETH now and get 5x as much.
Of course this is all hindsight - but it does show the dichotomy - the strengths and weaknesses of both. If you had lots of capitol and were willing to take 100% loss people should have bought coins and not mining eq. If they wanted to just put 1 foot in the crypto ocean - they build rigs.
Here's hindsight - ETH had fallen all the way to $10, even $7 during last January when DASH starting during it's insane rise. Nobody wanted ETH (well except the believers - Polo trollbox chat showed this). If you bought then you would be up 30x from just holding 6 months longer than somebody buying in July. That's why it makes sense to look at the big picture.
ETH is the perfect of example of a coin that you shouldn't have mined (even though I did). If you bought the coin at launch is was sub 1 penny. You could never mine as much ETH with a single RX 480 going full tilt to today as if you had spent all the money on the coin at ICO.
So - if you expect the coin to fail mine it. If you expect it to succeed buy it (at least well timed buys - doesn't take a genius to not buy ETH at 1500 or BTC at 20K+).
Miners really should spend time reading the speculation and investing parts of this forum. Sticking your head into the mining forums 12 hours a day seeing if they can eek out 1 more sol out of 1060 by changing drivers or tweaking with settings are missing the forest through the trees.
Bitcoin sat dead after hitting $1200 for 4 years with most of the world saying it was dead. It dropped from $1200 to $100. With all that idiotic ICO money thrown at scams last year, the ETH demand is just going to keep going down - it's a race to the bottom.... until some major trigger.
Buying coins vs buying hardware is a debate as old as the moon. I have never bought a single coin with my money. I only bought hardware. Sure, would I have bought ETH at 20$ instead of an entire rig that, before the ice-age, would have brought in like 0.5 ETH a day, I'd still be up 1000% today.
But what you are forgetting in you analysis, is that in contrary to coins/tokens, hardware like GPU is something tangible. People are much more likely to be ok to fork out 300$ for a GPU they can hold in their hands than some coins they can never actually touch or hold. you can't deny that cryptos, all of them, are still a very risky venture. Even ETH at 200$ is still risky. Hardware on the other hand has a value depreciation you can estimate pretty easily over a period of time. Hell I'm sure I could sell mine easily for a 100$ today while they will have paid for themselves numerous times.
Also not everyone is a trader and not everyone has a capacity to evaluate a good entry position (or exit position). Trading is not idiot-proof, far from that.
I'm not forgetting it in my analysis. Read the previous post I made. I said if a person enjoys watching the fans spin and is genuinely entertained by mining well then more power to him/her. You can't buy happiness, but you can buy enjoyment by subsidizing bad mining practices

I'm not here to take away anybody's enjoyment, but if you are in mining to make money it does not make sense to mine during a loss period.
Again please refer to my previous post where I said mining equipment is used a hedge against a coin's failure. You should mine coins that you think will fail. The ones you genuinely believe in you should buy because you're not going to let some market manipulation dissuade you from being part of it.
I've been mining since 2011. I'm old as dirt compared to most of you. I once had a farm that approached 0.5% of the BTC network when BTC was "dying". I know how much fun and headache mining can be. BUT... almost every mistake I've made so far can be attributed to emotional reactions and deviating from my plan I set forth. Crypto miners need to think with their heads and not their hearts for maximal profits.
I agree with most of your points, and even the buying coins not mining coins part - to some extent. Mining is more like financial planners tell you to do, dollar averaging in your investment. You never know what will happen to the market, and at what point in a cycle we currently at. What if the market is slowly dropping for 2-3 more years, and after that back to bull market. You will be hodling a large bag if you sell your equipment now and buy coin directly, you would be better off to buy it next year, or 2020? This is how dollar averaging works better for market fluctuation. But of course if you see the market recovering very shortly you should sell all your rigs and buy coins right now.
Anyhow mining with loss is always a dumb choice, unless the guy enjoy happiness from it like you said.