These sorts of changes aren't there to make the 5e ruleset capable of functioning on a computer. It is made because Larian wants to make DoS 3, not BG 3. That want to reuse assets like surface areas absolutely everywhere, regardless of what 5e says about that. They literally named 'flanking' into 'backstab' because that's what it was in DoS, rather than the term used in 5e. They are trying to use Directional Facing even though the rules of 5e specifically reject it.
Why not have both?
Homebrew a "lesser fireball" that works by d6 aoe damage and maintain the normal firebolt.
In every game that I've played, firebolt is single target damage... Diablo 1, all D&D products, Might & Magic VI~VIII...
