it's not strictly a math problem, because human behavior plays a big role in how it plays out actually.
157 million tx is the rough capacity of the bitcoin network on-chain. how many on-chain transactions a person needs to do per year to use lightning? 1 on average per year? 2? i'm using a channel made many years ago, but before that i opened and closed many. how optimized this can get in the future? will channel factories be a thing?