A useful way of thinking about it is this: What would happen if the block time were infinitely small but latency was not? Nodes would all have solved their own new block before a block from a peer showed up— each node would be its own network never (or at least infrequently) to converge with anyone else.
The same applies for speeds which are fast compared to latency: They cause long delayed convergence events. The particular number for 10 minutes is debatable... there is nothing that gives you that particular value .. it's just a security/scalability/network-radius vs confirmation speed tradeoff.
The infrequent blocks also keeps costs down on lite nodes which must process all the headers.
I found a post you made recently that i thought was interesting:
…Not to mention a zillion other less workable ideas that are waiting for some breakthrough or another to make viable… mostly I try to spare the public the more inane stuff... and certainly I've had no shortage of imagination for all the technical and economic failure modes that can result from removing part of the scarcity that drives a cryptocurrency. We've even had non-blockchain scarce altchains— Liquidcoin (for speculation)—, perhaps you don't remember because it imploded into complete non-convergence before half the people who wanted to run it even got it installed (though its 'innovation' was uncapping the block rate instead of uncapping the blocksize).
So by lifting the block generation rate this currency imploded? neat.
