I've seen this finance meme over and over again, and it's mostly an irrelevant argument. Yes, of course interest rates affect the valuation of growth companies, but a successful startup might grow 1000x from early investment rounds to the time when it's an established company with lower growth and a world-dominating role in its domain. An interest rate increase on the order of 2% is laughably small in that context.
What's probably going to happen is that valuations will be a bit lower at all stages, but why should that affect motivations and outcomes? The most motivated people aren't primarily in it for the money anyway, and there is plenty of room for getting rich.
Tens of thousands of people got rich after the dotcom crash, and interest rates were much higher back then. Interest rates are just a minor scaling factor.