They are not selling the tools anymore. They have new versions with new batteries. In most cases higher voltage so at least there is some technical reasoning behind it but not always.

There already is standardisation, of a sort. A lot of these things will just be a bunch of 18650's in a fancy box. As long as you can get into the box, you can replace the cells.

Rather than standardised boxes, I'd settle for manufacturers just using accessible screws to hold the battery together.

How long does your avg heavy use 18650 last? 9 months?

18650s are the absolute perfect example of this. Great little batteries.. for a few months.