It definitely seems like they now have a far more precarious balancing act, they need to give you more for the money now for these products to make sense, but they're inevitably going to start treading on toes and putting pressure on the other OEMs who I'm assuming don't have huge margins to work with to also be upping their game... For the SL 3 15" the lower two tiers are already quite competitive, while the upper two could probably just about get away with doubling the storage amounts without completely destroying the Dell, HP etc midrange offerings. This would make the £1,699 SL3 the most rounded with the Ryzen 5, 16GB and 512GB - that compares to an e.g. HP envy 15 which comes with 4k,i7,16GB,512GB and an MX250 for £1,499 so still has a competitive advantage.
The real issue I think is going to be the Surface Book 3, if they're matching the approximate spec and price of the MBP again, then it's probably going to be something like an i7-10510U (4 core, TDP up to 20W for the tablet section) or maybe even a 10710U (6 core equivalent) - in the case of the latter as it's 10nm so gets more out of its TDP, that's actually not far off the performance of the full fat 6 core i7 in the MBP, raising the configurable TDP to 20W again would probably help with the sustained performance, too. And then RTX 2060, 16GB RAM, 512GB storage, for around the same 2,399 as the MBP - that actually starts getting quite competitive with an XPS 15 which only has GTX 1650 graphics and only a 1080p screen below the ~2,000 mark. Starts trampling on Razer's basic blade configurations as well. I suppose the base SB3 15" might come with a 1660 with the 2060 reserved for the 2700 and 3K+ models? Starts getting a bit convoluted then, though and like you say these need to be products that stand on their own - in all a bit of a headache for MS.