Cloud pricing is strange because it's not based on reality or cost of providing the service at all. It's also clearly an anti-competitive market once you understand that.
Short answer is that the big clouds are trying to make a profit - a large profit - and competing with each other cuts into that profit & devalues the market. If the market isn't lucrative enough, the big clouds will have less priority to push their clouds and everyone loses.
There is no other property here.
Reliability/redundancy is not a factor. (Routers & switches don't cost much anymore)
Performance is not a factor. (Do people really think they don't get their bandwidth almost free through peering?)
It's all profit.