So just because web pages work well for someone who recently spent $600 and up on a phone doesn't mean that it's not worth optimising them.
To give you an idea of how divergent it has become, try:
This is the benchmark most representative of Discourse performance, and the absolute best known Android score for this benchmark is right at ~400ms on a Samsung Galaxy S6. That doesn't seem too bad until you compare..
iPhone 5 â' 340ms
iPhone 5s â' 175ms
iPhone 6 â' 140ms
iPad Air 2 â' 120ms
iPhone 6s â' 60-70ms
In a nutshell, the fastest known Android device available today -- and there are millions of Android devices much slower than that out there -- performs 5Ã-- slower than a new iPhone 6s, and a little worse than a 2012 era iPhone 5 in Ember. How depressing.