I quite seriously suspect that answer will be "24 hour electricity and grocery stores where you can buy food from anywhere in the world"
> Our widespread and normalised alcohol abuse
Until pandemic we've lived in a fairly teetotaling era. I suspect for the next decade we'll see an increase in casual drinking, becoming more similar to the 1950s. If you watch any films from that era very strong cocktails are basically a standard for just about any social occasion, any time of the day. The pandemic has instantly changed peoples views on alcohol and other drugs, what's coming the immediate future will likely continue this trend.
The immediate future generations will likely look back on ours as a bizarre blend of incredibly wasteful prudes. A generation of people who gluttonously destroyed the planet while at the same time being too timid to let themselves enjoy it. I think the reaction will be a large one of revulsion "you destroyed the planet and you didn't even let yourself have fun doing it? you lived at work for what?"