Nvidia has been a top-performing AI stock over the past three years.It's easy to be a pessimist about any sort of investing trend. Skepticism always sounds smart in the moment, but optimism tends to make investors more money over the long haul. One of the biggest stocks that investors have been skeptical of is Nvidia (NVDA -4.84%), as they are worried that this stock could end up just like some of the dot-com stocks that crashed after the boom was over.However, Nvidia is a much stronger business than those, ...