Lets say you have a 500Mbps connection (most have higher). You're already sharing that with 9 B41 carriers (3 carriers / 3 sectors). Up that to 6 carriers/sector and you've got 18 B41 carriers to support. Assuming equal load balancing (1 connection per carrier), that reduces your possible throughput to ~27Mbps per carrier. To be fully effective, each carrier should have full support from the backhaul, which would require a roughly 1.5Gbps connection. And that's not considering the B25/26 and 1x/EVDO connections.
No, backhaul equal to 100 percent of maximum airlink capacity for multiple carriers across multiple sectors is not needed "to be fully effective." All carriers and all sectors running at full bore simultaneously never happens. Never, not even close. Provisioning backhaul at the 50 percent level for aggregate airlink capacity should be more than adequate.
There certainly are a lot of different forms of lossless. Tidal, from what I've read online, is preparing to begin streaming MQA, which I've also read is going to reduce bandwidth.
I am a Tidal subscriber. Tidal already is streaming MQA from its desktop app, not its mobile app. And, no, MQA, will not reduce bandwidth. Rather, it will increase bandwidth. The standard FLAC container for MQA is 24 bit 44.1 kHz or 48 kHz.