Be nice if they could add a DnD 'Standards' mode. Maybe in a patch. Afterall... less than 2 weeks to go... little late for them to add or change too many stuff now for the actual release.
Not a ton of reason to do it. Just look at core difficulty in pathfinder games. There's few rules purists out there and even fewer 5e rules purists, you probably just end up upsetting casuals who wouldent know what "standard" means
Also since theres a lot of environmental hombrew in larian games trying to full phb with it probably won't work at all