I have a 2019 RX350 which has failed to accelerate and stalled on 3 different occasions. About 1 year ago and two in the last 2 months.

car shop says all six fuel injectors need replace and recommends a spark plug change

car has 47000 miles on it and is driven as a grocery getter for the last 6 years and maintained.

fuel pump was changed with the recall in 2020.

any ideas on if this diagnosis is correct?

I would get another opinion from a more trustworthy shop.

If the injectors and plugs are the problem (which is very doubtful), then there would have to be an underlying issue. How could all 6 injectors and plugs go bad at the same time and at such low mileage? Definitely get a second opinion and make sure they scan for codes.

That doesn't sound likely, I'd take it somewhere else. Typically injector issues are consistent. and your not due for plugs for at least another 40k.

Helpful to know what state you're in. Powertrain warranty is 6/70 and this car may still be covered. Even if not, if you are original owner and have done dealer services, it's close enough that I would have dealer diagnose and ask for goodwill coverage. At worst you end up out $200-300 for a second opinion.

Reason I mention states is that CARB states have injector coverage for 7/70. Pulled this from the 2019 RX350 warranty and services guide on Lexus website.

Personally I don't know if injectors are the issue, it seems unlikely they'd all fail at once. It's also very hard to diagnose without knowing what codes it's throwing.