It was bad timing. COVID hit. That killed of projects for a lot of brands.
While you're right about the COVID impacts, I don't think that is the excuse here. The depth and breadth of Toyota's lineup has exploded over the last 7 years while Lexus has been stagnant and lost key models. The LF-1 would have been a platform/parts sharing exercise with the LS and LC, so most of what was needed to make it happen already existed, but Toyota chose to consolidate their resources and save their money by trying to upcycle FWD platforms like GA-K.
Toyota's own Century SUV - the crown jewel of the entire portfolio - is built on a FWD chassis with a 20 year old V6. If that doesn't tell you everything you need to know about Toyota right now, I'm not sure how else I can help. They didn't even put it on their most premium unibody platform - GA-L - or put their latest and greatest engine in it, the V35A-FTS.
Toyota's leadership in Japan lives in a vacuum where all of the roads have a 35mph speed limit and they all think that because they engineered it, it's the best product in its class. Toyota execs would do well to spend time in America and Europe, and drive the latest Mercedes, BMW, Audi, Bentley, and Cadillac products. It's clear they have no idea what is really going on and are incredibly ignorant and shortsighted.
I have a theory that the Century and GR GT may very well fail here and in other global markets. It's almost like there was a specific reason why Toyota created Lexus, and spent 36 years building a luxury brand...