tl;dr: the old "bitcoin can only do 7 tps" argument, except with an extra bit that says even with layer 2 scaling, if each user has to transact once a month on-chain (because... salaries?) then max users is 20M (which is 7tps multiplied by 1month). All in all, not very interesting because there's no reason why salaries can't be paid on l2 as well (securely as well, if LN is used).
So thought experiment: the incentive to stay on L2 is anonymity & lower transaction fees. Therefore as usage goes up transaction fees will raise but more will be pushed to L2 in order to avoid those fees, & in effect reducing them
So let's say things have exploded: transaction fees are twice my salary. If I get stiffed on L2 I'll have to pay more in fees than my salary. So my recourse will be to sue my employer into paying the transaction fee
