So a lot of coins are held by exchanges and you know: not your keys - not your coins, this isn't silly expression, it's true. Nothing to talk about that, bitcoin mining is 100% turned into commercial business because of increased difficulty and not revealing new miners on time makes it almost impossible for simple people to mine it.
Majority of the coins are held by gambling sites who started during the 2014 and then comes exchanges and web wallets and even with the risk involved in storing the coins in exchanges people do tend to take the risk even though they hear about massive hacks year in and out.
When it comes to mining, it was a commercial entity back in 2013 as people need to have block erupter to mine and then the ASIC came into the scene and if anyone thought home mining was the way to go to have a truly decentralized network, now we are seeing the opposite as a few huge mining farms control the entire network.
Everything that's good at first gets abused and finally bitcoin isn't exception. But after all, bitcoin has 100x more advantages than current money system.
It's still more decentralized and it has fixed supply, blockchain technology. No one can edit 21 million bitcoin and no one can mine bitcoin on their own after reaching to that limit. We don't depend on 3rd parties, i.e. banks. It gives you possibility to feel a little bit independent from current money system.
The 21 million bitcoin cap can be removed if the developers wanted to
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