Pfizer and Moderna vaccines are both based on mRNA technology, which is relatively new, but Pfizer is a bigger and much more experienced company than Moderna, so Pfizer definitely had a head start when the vaccine race began. I don’t like the impractical freezing required either, but that’s the state of that particular tech right now.
China was able to get ahead quickly with their Sinovac vaccine because they didn’t fuck around with fancy tech. Their vaccine is made with dead viruses, pretty much the same way as the annual flu shot. It also doesn’t require deep freezing and stay usable for years, making it suitable for Third World distribution. The efficiency isn’t as high as Pfizer, but even so, there’s a practical “If it ain’t broke don’t fix it” lesson there.