Many native apps still make sense as they need deep access to phone features or better performances (games). Many apps are already backed by a website used for acquisition and first engagement (and then pushed to install the app). Both worlds have not been so disconnected anyway for the developers standpoint so they should be able to adapt easily.

The question is more tricky regarding CPI ad networks or app analytics services. CPI ad networks will make less sense because the Installation disappears. Web technologies will make SEO easier for developers (app indexing was not easy) so paid acquisition and SEO will be back in competition... which should lower the ad spending. Retention remains key and app analytics and mkting tools (like push notifications) have acquired a great know how about managing users during their lifetime. So they should stay too.

Like in the 00's when developers had to adapt their skills from Windows software to web technologies, I assume native apps developers should start updating their web skills. It's hard to find the right guy for developing a high quality PWA right now.

Thanks for your response As you said its hard to get a guy a who develop quality PWA .I think there is good job opportunity