Re: It's a pyramid scheme by design
Okay, you're conflating some things and otherwise spreading some half-truths. Not that I'm saying your criticisms are necessarily invalid, Bitcoin's long-term future is uncertain. But a few important points:
1. "Pyramid scheme" really doesn't apply, except in the loosest sense that people who got in early of clearly benefited the most. But that's just a natural result of how things worked out. Suddenly people started considering it valuable, obviously the risk-takers who spent effort or money to get some while it was still unknown are now in a fortunate position. You're more correct about the deflationary aspect, that's intended, and I do have some doubts about that being a good idea.
2. There are two factors which make mining less efficient as time goes on, and I think it's important to note the difference. Every four years the reward drops be half. That's pretty steep I agree. But the other thing, which is by far the bigger factor, is that the difficulty automatically adjusts based on how fast people are mining, calibrated to keep blocks being added at relatively steady six-per-hour rate. This shouldn't be a problem because if people start to lose interest in mining it will automatically get easier again.
3. As above the mining reward is cut in half every four years, but miners also collect transaction fees. Currently it looks like they're taking in about 0.25 BTC (roughly a hundred bucks) per block that way. That's only 1% of the current mining reward, but as long as people are using bitcoin it will never drop to zero.
In short, it's imperfect and who knows what will happen in the future, but it's not as horribly broken as you make it out. It's also not set in stone. If the bitcoin community can be convinced that it would be in their best interest to change something, it would be possible (though disruptive) to do that.