With all due respect to Mike Mearls, he is wrong. The action economy in 5th Edition is beautifully designed, and I wouldn't change a thing about it.
Indeed he is wrong... in fact I would greatly disagree with everything he has suggested lately. His Initiative system is a ridiculous idea -- taking us back in time where we have to pre-declare actions. 6th Edition? No... 5th is working perfectly fine thanks (with a little room for tweaking here or there). Bonus actions are also working fine. Maybe its time for Mike to retire because he has clearly lost touch with what makes the game great again.
What Mearls implies that bonus actions economy is a huge thing in 5e, especially in bigger levels, where a PC has a plethora of class options, spells, whatevers available. And this in turn means that a PC must choose what and what not to do as a bonus action.
This contradicts with basic aspects of 5e; ease of use and speed.
For me personally, this is not a bad thing; action economy is one factor that can help players make strategy in the game and I like that. But on the other hand it is not that cool from a designer's level to prepare class options that you know will contest each other on what will happen within each round.
Ditto!I'm ready and formally asking for 6th Edition
They pretty much only exist because, late in the playtest, they wanted a way to limit extra attacks granted by various classes.
They snuck back into the edition that way and got used for a whole bunch of extra stuff in the process.
Personally I think this is more often an imagined problem than a real one.