We have a B2B booked - first leg with a TA and the second, direct. The first, we just received the printable tickets; the direct booking, MSC sent us the QR codes for the boarding passes. On the app, the boarding passes indicate that the QR code will be available on embarkation day.
My issue is that, other than the app, there is no longer printable proof of what is included in the booking. Having had issues in the past (where, thankfully, I had printed off what we were entitled to) I’m not keen on this set-up.
While I won’t have an issue with the digital boarding passes on my phone (whether at the port or for flights), I would always print everything possible, too.