The following are the OS/Browser combinations that are compatible with the Add to Home Screen functionality that makes Progressive Web Apps possible:
These configs represent about 85 to 90% of all Internet traffic. So overall support for PWA is widespread. Notoriously missing is Firefox, which dropped support for PWAs in early 2021. Safari only supports for PWAs via custom Add To Home Screen instructions (out-of-the-box in Progressier!) on iOS. That means that you won't be able to install a PWA on MacOS via Safari (but you can with Chrome). Chrome on iOS also isn't supported.