Subtotal On/Off Options Needs to Be In Subtotal Section
The slider turning row/column subtotals needs to be in the subtotals section, where most people will think to look for it.
Either that or put it in both places (general and subtotals).
This is a must to decide which of dimensions should have subtotals and which not. Right now you can only have subtotals for all dims, or any of it = grand total for the column/row is not available too. This should be changed.
It could be a duplicate, https://ideas.powerbi.com/forums/265200-power-bi-ideas/suggestions/13658727-toggles-for-sub-totals-and-grand-totals-on-matrixe.
There are other requests of this nature (to which I strongly agree), but the one I've linked is well defined and already ahead in votes.
Let's hope it works.