To expand on my previous post, I really do wonder how they will position and differentiate RX, RXL and LF-1, specifically. GX is an easier one, being BOF with a completely different personality.
Lexus is pretty good at building cars that look sporty, even if they don't exactly fulfill that proposition dynamically - NX and RX are great examples. RX also has a great interior, is "right size two row" for most people, and the V6 is decently peppy. There's also the hybrid. And an F-Sport package.
Even if it is RWD and marketed as a flagship vehicle, I'm not sure how much of a case there is for the LF-1 above the RX if they are similar in size. Keep in mind the next generation RX will move to TNGA and adopt the new Dynamic Torque Vectoring AWD, as well as next gen powertrains and tech. Every other model that has been redesigned on TNGA has been a huge step up, so I think the 5th generation RX will be as well.
In fact, I think of this much like the ES and GS (while spwolf is sharpening his spear and looking up my address) debacle. Lexus thought they could differentiate them because the ES was the "entry level luxury" model while folks wanting sport would opt for a GS. Reality set in and people weren't willing to spend $10-15k more to get RWD, when many of the other execution points between both were similar.
Perhaps the best case is for the RX L to only live for this generation, and for the LF-1 to be a true three row vehicle to match up with the GLS and X7.