Short answer: No. Medicare.gov says people who get Extra Help do not pay a Part D late enrollment penalty while they have it.
Medicare.gov states plainly that someone getting Extra Help won’t have to pay a Part D late enrollment penalty while they get Extra Help. For a lower-income person who went years without creditable drug coverage, that alone can be worth the application.
The relief is tied to having Extra Help, so it is one more reason to screen every lower-income Medicare person, including those who never enrolled in Part D on time.