It always seemed like a bandwagon thing. I never really understood how the hell it worked, and I'll bet the people who invest in it don't, either.
I largely ignored it until I had to get up to speed for work. It is extremely energy dependent and I read recently that more energy is used worldwide for cryptomining than real mining.
The process is simple. To be a cryptominer, one must first validate existing transactions ( the blockchains), then solving mathematical problems first. only the first to the answer gets the prize, so speed is key.
The technology has been evolving quickly. They soon realized graphic cards could solve things faster, and then specialized graphic cards developed.
Miner now down to a calculation. Top of the line tech from 6 months ago is barely profitable today.
Many people do crypto arbitrage. There are a number of exchanges around the world and prices vary between exchanges. So, they buy in one and sell in another.
But it is the laundering that is huge. Funds that banks can't take (from illegal sources or gray areas such as marihuana) are changed into crypto and then sent around the world.
Crypto is mostly being regulated as property not currency, but may change.
From those I know invested in crypto, they are often frightened or elated. It is a rollercoaster. I read somewhere that 90% of crypto trades are fake, with the buyer and seller the same and they are just trying to move the price.
Now a lot of currency exchanges are fake, anyway, as the traders manipulate the prices to get the price they want working together. As such, it isn't surprising that crypto exchanges are equally bad.