Alphabet, Google's parent and briefly the most valuable company on the planet has a market cap of 510.2B USD right now.
And no debt to speak of, I think. Normally you need to add the equity market cap and the debt to get the total financial structure of the company. (I just googled, and I think that sum is called the `enterprise value', if you subtract any cash holdings.)
You're talking about one of the most successful companies in the history of business, in Google. Their speed to their present scale in terms of profit - from founding to now - is unprecedented. Add to that that they make most of their money from operating a hyper-margin software service in terms of costs (with nothing at all similar to Uber's drivers and regulatory problems), one that has been almost entirely unregulated (until now) and that also happens to be a quasi-monopoly. Using Google as the standard for what Uber could achieve, is extremely far fetched.
I really think that this isn't the place to be playing rhetorical games. I think discussions would be much simpler and clearer if people state their points clearly and unambiguously.
Presenting the evidence to help people come to their own conclusions can be more effective than hitting them over the head with a hammer.
My point was ambiguous to begin with: yes, Uber might very well grow to a trillion USD in valuation, but doing so would give it twice the market cap of any other company so far.
$100B sure. $1T ... maybe if you wait a while to let inflation catch up.