Extreme example has been Twitter.

Twitter PWA: 600KB

Native Android Twitter: 23.5MB

https://developers.google.com/web/showcase/2017/twitter#lowe...

This has been a huge differentiator in countries where users are sensitive to data consumption, which is why you see many case studies about countries in India, Africa, etc. getting great traction with PWAs.

Disclaimer: I'm on Google Web DevRel team

Storage space isn't generally the bottleneck on older devices- it's the CPU/RAM. On that count, native apps are usually overwhelmingly preferable.

If these catch on a big way, it'll be catastrophic for more underpowered devices. Modern web pages are already starting to get acutely uncomfortable to use on older iPhones, let alone older Android devices- we aren't yet at the point where performance levels are high enough that we can slap the equivalent of an electron wrapper on everything, smirk at users' devices' vanishing battery life and call it a day.

Apples to oranges. The download size of a native app, while important to keep low, will have minimal effect of the actual user experience post-download. Web applications will in almost all cases be a strictly worse user experience.