I am sure. Unless, of course, application programming and software development has changed so much since I left the field and computers have regressed, which I doubt. The only changes that would need to be stored are those made to the already existing parameters that are found in the brush editor. A 32 bit register can hold any one of more than 4 billion unique configurations. I doubt that however many parameters there are in the brush editor that they would total more than that. And yes, some of the parameters are not on off switches and can hold any one of a variable set of values but even then I doubt all possible configurations would reach 4 billion, and what if they did? Then use two registers instead of one and more than 18 quintillion unique configurations can be stored. 32 bits is .0004% of one megabyte. Saving the name and current state of the last selected brush is a no-brainer. Saving the current state of all changed brushes for the duration of the current session is a no-brainer.
The hurdle here is not one of processing or storage overhead.
Anything that is done would be an improvement over the current broken implementation. If all I could see was the name of the last brush I selected whenever I choose the brush tool, then that is an improvement over just looking at the brush panel and trying to remember what brush I was using last.