Yes Lexus should do that, because others do, even if I dislike this concept, because it makes no logical sense if one can change cars from a single brand that has the same cars. Lexus should also this program to get a Toyota. What is if you need a Tundra for a while?
I personally hate this concept for many reasons.
1. It is a "consumerist" concept, where the buyer always looses. Pay, you have, stop paying you have nothing. Change all the time and get the latest, even if it is not the best. Who needs a solid and reliable product, when you'll change before it breaks or is worthless?
2. If the goal is to have a vehicle at disposal for each situation (i.e. a pick up truck for the boat you tow that day, a limousine for the day you drive your clients, a sports car for track day or mountain road trip, etc.), then the products are really bad in almost all cases, because they are all redundant and offer very little diversity. A sports that is not a single car, does not need to be compromised by comfort, tech and practicality for example, as is the case with Porsche 911/718. A pickup does not need limousine luxury carpeting and leather dash if it is used for "dirty" stuff, and so on. But what single brand has a car for each purpose? Except Mercedes (and who knows how their program works: can you get an AMG GT or AMG GT4 and a Sprinter?), no other, unless you consider TMC one. Volvo has 3 SUVs and 2 sedans/wagon. I see no benefit in being able to change between any of them.
Lexus has 2 coupes, 3 sedans, and 4 SUVs/CUVs. Basically a sport(y /-s)car, a daily car and a utility car. If the ideal garage is 3 cars, it is better, easier and cheaper to take the best car of each car category cross-shopping all brands. The most used car on a daily basis is the most important one, and the one that will change more often because of use. Why change the other ones if they work fine?
Such programs, for consumers (not professionals) are money grab and only benefit the company (if it works). The customer always loses.