Anyone can raise his own mining pool, and add this in the following list of working mining pools: https://miningpoolstats.stream/armor
or somewhere else.
Miners prefer to do mining on the pool, with largest hashrate, to prevent orphan blocks on the small pools.
But need more pools, to prevent 51% attack on the network.

As you can see here: https://www.blockchain.com/charts/pools
no one pool have no more than 51% hashrate of all the bitcoin mainnet.
So need to diversify the network hashrate, in the long-term, to make the decentralized network more stable,
and new mining-pools are welcome.

In the future need to diversify trading too, to prevent concentration more than 51% trading volumes.
So new exchanges are welcome too.