So it is possible that a LN "takeoff" is more likely to come from a new increase of transaction fees due to fuller blocks (condition 2). This would make it again attractive for service providers to jump on the LN boat.
I'm afraid that's not going to happen. If fees reach 1000 sat/byte again, opening and closing a LN channel is going to cost $25 or (much) more. That won't be worth is, just like I couldn't use Bitcoin for normal transactions at the end of 2017.
Unless you can use an exchange to buy Lightning Bitcoin directly so they open large channels instead of having users open small channels, but that means you can only use custodial wallets.