I wouldn't say unproductive. Some of these companies will continue without further funding. A lot of the ones that don't will have broken new ground, educated themselves further for another go or are ending up at a big company either just as an aquihire or actually selling assets to the company.
I don't think so.
Of the companies that fail at series a, a small portion of them will be most desirable for big companies and will get aquihired. There will be plenty of super talented teams with great tech that don't get the product market fit or the market turns out to be too small or crowded to get a series a.
