The problem here is that dev's don't want to invest in iPad apps as it's a strain on their teams and network (having to keep up with 'another' platform) and Apple has no interest thus far to open up Safari so that 'real-work' can be done on it, like you know, with how people in this day and age use a computer for. Squarespace used to have an app a few year ago I believe but then they ended development for it. I would say its one of the main areas in which the iPad is held back for me because I constantly need to edit portfolios and make changes to clients websites on the move and thus I can not carry about an iPad solely - as much as I would love to.
I agree with you that it seems that Devs are not always motivated to work on iOS apps. It is a strain I agree. I wonder though how they can be motivated to do more you know. I do have Development background but I have not worked with iOS as it requires Mac machine and I don't own one. That is one restriction though. Like if you want to develop apps for iOS you need to have Mac. Now in USA I assume this might not be that hard, but it's definitely not the case in my country or Europe in general. Macs are expensive so they don't buy ones. Only designers or iOS developers (which are for mobile apps only though) work on Macs.
There is a lot of outsourcing when it comes to Development. Business. People prefer to establish their Development centers in countries where salaries are lower and the standard is lower. When the standard is lower though, people do not work on Macs.
I am not sure what's more disappointing, the fact that Apple haven't opened up Safari for all these years or that it will keep us waiting for the supposed iPad OS update 13 in summer - and by the time it's released, new iPad Pros will be round the corner - putting all that power to waste.
You never know they might skip introducing new iPad Pro next year .