Less waste means less waste.

You can carve a guitar neck out of a single large piece of wood, but 60% of that piece of wood turns into waste.

Or you can glue three much smaller pieces of wood together, and 5% of that wood turns to waste.

It takes longer to make less waste.

I guess define "faster". If it means getting to product/market fit earlier, agile is your guy. And that could mean eliminating waste so much that it's just 2 devs hacking on an mvp, testing it with real users every few days / week, adjusting the mvp to solve the users problems better each time, with 0 distractions.

If it means delivering features faster, whatever they are, to make an executive feel better, agile will not help you.

Not really. Less waste means not spending time on non-essential features. That doesn't mean that the core features people are focused on will go any faster at all.

Someone (product owner) should be prioritizing the core things needed to be delivered which means you don't waste development and testing cycles on things like an extra button on the MS Office ribbon bar that does a hardly used feature.