Both the Overview and Post Editor dashboard sections seem vulnerable to problems - typically described as bX code terminations. Many of the people reporting problems admit that they are using Internet Explorer V8.
For some blog owners, the choice of staying with IE V8 is not an option.
Get everyone to use Chrome, and don't support those using IE V8. Win XP works fine. Everyone can't get new computers or operating systems, every time some new software comes out!Unfortunately, Windows XP was sunsetted, by Microsoft, some time ago - and IE V8 is the last version of that browser that will run, on Windows XP.
Windows XP and IE V8 may be "good enough" for now - but time is running out, on both.
Blogger, like every website on the Internet, is going to design their displays and wizards - such as Post Editor - to use features provided in the newer browsers.
As Blogger fixes problems, like the recent problem with the Post Title, the more browser versions they have to support, the more complex their code becomes. Besides fixing problems with Post Editor, Blogger will be developing new features - like Google+ Comments, and the recently added "Blog Posts" option to "Show Author Profile Below Post".
Each of these changes - the recent Post Editor fix, Google+ Comments, and the new "Blog Posts" option - must include code to work in all supported browsers. The more browsers supported, the more complex the Blogger code becomes.
Owners of older computers, with less bandwidth and memory resources, are going to notice Blogger - and other websites - requiring more resources. As the Blogger code base becomes more complex, the amount of code required will make the increased resource use more obvious. Many people have already noticed Blogger running slower, when they edit their posts.
As Blogger code becomes more complex, and as they support more browsers, it's going to take them longer to develop new features - and to fix problems with current features.
The only answer here is that Blogger simply can't support an infinite number of older browsers. As newer browsers, with newer features, are made available, they have to stop supporting older browsers.
It's possible that Blogger is currently making an effort to temporarily override their earlier stated browser support policy, so they can accommodate Windows XP and Internet Explorer V8 - but it's unlikely that they can do this, forever.
If Blogger fixes the current flood of bX code errors, for users of IE V8, this may not last, for long.