It's probably the company that has had the most concrete impact on my life and the lives of my friends of this generation (depending on how you define generation).
Can you give an example of what you think should (???) be the most important company of a generation?
first, I would push back against the idea that Uber has vastly increased mobility. It's made mobility slightly less annoying in certain places for certain groups of people. But most parts of the world have had taxis for a long time. You've been able to schedule a taxi for decades, something which Uber just recently added. Prices are a bit better with Uber, but it's unclear if the VC subsidized pricing is sustainable. In places like Cuba and Cambodia the taxis and tuk-tuks have been excellent and painless methods of transportation for generations and often require zero wait and have zero barrier to entry other than the price of the transportation, that is; it requires to smart phone, no data plan, no credit card.
I don't perceive Uber as having done anything other than contribute a level of convenience to transportation. I don't feel as though it's provided mobility to anyone who didn't have it before, it hasn't decreased congestion or pollution. How many lives has it saved? How many people who desperately lacked needed resources has it helped? How much has it decreased dependency on non-renewable resources?
I think companies that provide life-saving resources to people or companies that increase equality are much more important. Creating the technology to get everyone access to clean water or drought resistant crops are some ideas that come to mind.
I can recall a number of times waiting on street corners trying to flag a cab for an hour, only to give up and walk home. Calling the taxi company on a busy night was a joke.
At least in this city, transportation was broken. Clean water and draught resistant crops are great in general, but on a personal level I'm still drinking and eating more or less like I was five or ten years ago.
Also, Bart allows bikes, San Francisco is always pretty pleasant riding weather, the busses are robust and have provisions for bikes, there's an assistance program for public transit in the bay. But damnit Bart why can't you have 24 hour trains.
I spent six months (Nov '16 - May '17) with my license yanked away after a seizure. Uber (and Lyft) changed my life at that time. The last time I was in a similar position I depended on friends' charity. There were taxis that you could call by phone, but around an hour away. I was in a large city then too (Atlanta).
Now there is an easy, cheap, fast, and reliable way to get anywhere in the city, any time I want, without planning ahead. That bar my friends are meeting at that was two busses away and not worth the hassle on a Tuesday? I'll be there in fifteen minutes for the price of my first beer. For those who drive: no more worrying about parking or how many drinks you had.
Ranking companies which had less impact on my life than Uber seems like a strange exercise.
Beyond that, Uber's usefulness really depends on locality. There are some places in the world that actually have functioning, acceptable taxi systems, like Seoul, where the prices are reasonable and the drivers are generally fair.