Bamboo seems to expand too fast and burn alot of cash through their expansion. Heard that they planned to launch KIX and MEL as well but quite surprised that MUC will be launched first.
I am skeptical about them being profitable, Vietnam's market has been suffering from overcapacity for a couple of years. I believe most "profit" come from sale and leaseback transactions not their operations.
As QH doesn't receive anything from their direct orders (10 789s with Boe), I don't think that QH can get anything from that SnLB game.
However, its service is so damn good. I flew with Bamboo twice. Those ex-Primera A321neos were fresh and new, the seats seem acceptable with Asians (at that time QH's A321s were configured C8Y198). The foods were perfect, crews were cute and friendly. I was also impressed by Bamboo's on-time performance (OTP) and its tickets' price. Bamboo has the highest OTP rate of all Vietnamese carriers, about ~93% (quite impressive with a 25-aircraft carrier). About the price, the tickets cost 2/3 as comparisons to QH's main competitor - Vietnam Airlines. There is no big difference between VN's and QH's quality of service, and QH is threatening VN by its cheap tickets.
On the other hand, one of its main weaknesses is entertainment. No IFE-screens installed on their A320 family-aircraft (I heard that Bamboo installed W-IFE on their aircraft [using your devices accessing the library through internal wifi], but not enough to satisfy you). Even the 789s, the IFEs were only enabled on international flights, and LOL the 789s will only serve SGN-HAN-PQC [all domestic flights] until the end of this month when it launches PRG service.
Hope that Bamboo will success. Despite its awesome service, I am worried about its development plans. 50 aircraft this year; $5bn 777X order (alongside the 10 more 789 currently on order); firming up the MoU of 50 A321neo [and 20 more 789, holy cow]; launching PRG, MUC, KIX, MEL and especially LAX or SFO in mid-2021.