I'm pretty sure we still plan to have lights in our renewable energy utopia.

We don't need them as indiscriminately and wastefully as we currently have them.

We dont need a lot things. Lack of "need" has never stopped humans. Switching to renewable energy certainly won't change that.

When solar is providing us electricity at 2 cents / KWH, we will use them even more indiscriminately.

Well, for lighting the battery costs are more relevant.

But nowadays you don't even need to wire electricity to the place you want to floodlight, so yes, we will only use them more.

pesticides in rivers because of fossil fuels?

Your ability to read their post as well as your ability to reply to it is thanks to fossil fuels.

The food you eat is thanks to fossil fuels.

Your entire lifestyle, from heating your home to taking your medicine: thanks to fossil fuels.

If you don't like it, take your clothes off and go live in a cave.

Even if I wanted to do that I couldn't because everybody else's indiscriminate use of fossil fuels is destroying the environment I would need to sustain me. Literally the point of the article you've responded to.