The mempool is not a global state. It runs in the RAM of your computer when you run a full node. Most people have theirs set to the default of 300MBs, but I have mine set to 2000MBs, but I'm also running full RBF on my node. So if you send a tx at a higher rate, it'll either get replaced on computers with full RBF, or replaced on computers which are dropping low fee txs due to their mempool size limits.
The mempool is not a global state. It runs in the RAM of your computer when you run a full node. Most people have theirs set to the default of 300MBs, but I have mine set to 2000MBs, but I'm also running full RBF on my node. So if you send a tx at a higher rate, it'll either get replaced on computers with full RBF, or replaced on computers which are dropping low fee txs due to their mempool size limits.