This won't be a 2-3% issue for long: Windows 8 Pro and RT both have the same issue. Site developers will fix their code to be touch aware or lose access to far more users. The market will drive the fix.
I hope you are right, but I think even with the best possible conditions, we will see at best 10...MAYBE 15% marketshare within two years. This is assuming Microsoft keeps pressing developers and addresses the shortcomings of the OS promptly, Nokia sticks around and keeps making great phones and all goes well.
I don't think some people appreciate just how hard it is to gain marketshare when people have been firmly invested in one platform for years. As great as Windows Phone is, it still doesn't have many killer features that will convince massive numbers of people to defect from their OS of choice.
I do think we will see steady growth, but like I said, 5-10% growth over two years is optimistic, that would be a substantial increase over the LAST two years.
Developers and websites are not going to really care about making stuff 100% compatible and catering to us in large numbers until we have something more like 25%+ marketshare and I think thats at least 3 years away.
As for Windows RT, if the current tablet sales numbers are any indication, I don't think it will be any help at all in getting people to adapt to mobile IE.
The short term answer for us is still a WebKit browser alternative for Windows Phone, unless you want to wait 2-3 years to be able to view the non-mobile versions of every single website and be able to know with confidence you can operate almost any drop down menu on a site.
I know I don't want to wait 2-3 years+ while Microsoft stubbornly tries to make mobile IE and Bing stick. Give us some $#$%*@ options.