The problem with BCE is largely that it does not fit with the paradigms of ncurses and terminfo, not that it is problematic in itself. This is alas true of a large number of terminal things, from function keys through "cursor addressing mode" to erasure, whose ncurses/terminfo abstractions do not fit the actual ways that these work.
On both real (DEC) terminals and terminal emulators, background colour erase is settable off and on, with DECECM; so a full-screen application can set the behaviour and know what the colour is going to be, leading to more efficient screen redraws. The ncurses/terminfo model, in contrast, is that the behaviour is fixed on or off, and a boolean (named bce) in the database tells softwares which it is for any given terminal type.
In reality, it is the paradigms of ncurses and terminfo that are the problems here.
* http://jdebp.uk./Softwares/nosh/guide/commands/TERM.xml#MEAN...