Just imagine that tomorrow all the big mining farms disappeared. What effect would that have on btc? After the difficulty had settled, absolutely none. Correct me if im wrong but if there was a handful of compuers running the mining software then life would all carry on as normal. btc is like the internet, you take a big chunk out and it carries on as normal. One transaction would be verified every 10 min whether it was 100 miners or 100,000 miners.
Probably a price crash due to the ease of carrying out an attack on the network, given that they constitutes such a huge proportion of the network, it would definitely have a lot of repercussions. The security of the network functions on the fact that it costs more to attack the network than what you stand to gain from it. If all of the big farms were to disappear, an attacker has to outpace the rest of the network, which is far easier than outpacing the bigger farms that disappeared.
Are bitmain, antminer and all the big mining firms and pools leeches on the system?
- As they are so big, the difficulty is higher and it takes more power to mine.
- All the power is concentrated in a few players. Individual miners don't stand a chance.
- Chances are fees would be cheaper as well.
No. ASICs made Bitcoin more secure (and less in a way). Before ASICs, CPU and GPUs dominated the mining scene and if were to still be the case today, there would be large botnets profiting off Bitcoin mining as everyone has either a CPU or a GPU but most won't have an ASIC. The difficulty is in essence a measure of how difficult it is to mine a block or to attack Bitcoin by re-organizing the chain. Proof of work works best if it is significantly more difficult and expensive to attack the network than the potential profits.
Unfortunately, One CPU One Vote was never possible. You would have people running giant CPU or GPU farms sooner or later and that is akin to running an ASIC farm as well. Individual miners would probably not profit from that either ways.
Fees are a not dependent on any of the parties that you've mentioned. It is determined by the fee market where miners prioritize those with a higher fee and it is limited by the number/size of transactions that the miner can include. Whether we're CPU mining or ASIC mining will not make a difference to the fee market, it is purely limited by the capacity.