Yes and no. The Android Market was only a few months behind the App Store (paid apps took another year) but when Android started to take off, lots and lots of developers started to try to come to Android in a big way and some even experimented with being Android first. But they all largely failed. Companies that actively invested in trying to be Android-first for a paid app have largely failed or been relegated to a very specific niche.

First, I think it was because the tooling was so much worse for Android than iOS, especially in the early years. And Google didn’t bother enforcing or even really outlining any HIGs for the longest time. It didn’t help that every Android maker had its own skin for the longest time (that is mostly over now, except for Samsung and some Chinese phone makers — and I would argue Samsung has a distinctive brand now that people buy their phones for their interface. They don’t want stock Android, they want the Galaxy Android experience).

But then even when you did have hit phones, like the first Motorola Droid and the Samsung Galaxy S (where the Galaxy S3 was a huge moment) and better dev tools, you still didn’t have users willing to pay for apps or even IAP. And it is hard to justify heavy-investment into a platform that people won’t pay for if your primary business is selling an app.

It also helps that iOS users typically have devices that are updated more regularly and that iOS devices are supported longer. And or course, there are fewer devices to test (though far more than there used to be).

This is an old trope that's not nearly as relevant as you seem to imply. It is also the same problem Apple would have with laptop and desktops, but is really not an issue.

I, personally, believe that the platform has very little to do with that disparity of revenue at this point - but it is directly related to the demographic purchasing the phone. Android phones are often much easier to acquire with fewer financial resources. That is not the market Apple has targeted or has wanted to cater to in their quest to position themselves as a more premium brand. In some cases they may be and in others it is a marketing facade that people have bought into.

But, the reality is to deliver a good experience on Android isn't any harder than that same experience on Apple. Is it as financially rewarding? Probably not, again due to the difference in overall demographic of users. But I think it has very little to do with technical limitations or variances as described.