Can sandbox be for 2+ players already?

I feel like Riot's passive aggressive response to sandbox mode when they made it one person was fine back when the community was willing to take anything, but it's been well over a year and I think it's about time the mode is available for 2+ players (2 minimum). It's craxy how if I want to teach my friend how to play league I either have to have him turn on his share screen feature (which tanks his frame rate) or I have to join a normal game that doesn't have the luxury of free gold for items or infinite cooldowns on tp or his ultimate so we have to wait as we walk back to lane (cause we also don't have free regen) or we have to wait on his 120 second cooldown ultimate to finally recharge. I remember trying to teach my friend how to play darius in a custom game, and after a while we gave up because of how annoying it was to wait on tp, flash, ultimate, etc. Practice tool has always been a lack luster addition to the game due to it's single player nature that doesn't allow people to truly work on their skill of fighting other players and only works on very basic fundamentals that any player over level 35 should know. Even among other modes in other games, like smash bros, it falls super short. Smash bros allows you to use a controller to control the second player, or even up to 4 players, which makes it an excellent way to practice combos against real player while allowing free healing, game resets, etc, and it can be argued league would benefit a lot more from this due to the much longer wait times and need for gold it has over fighting games. I doubt we ever will get a 2 player or even 10 player practice tool since it won't make Tencent any money, but it really shows a disconnect when we still have a serious barrier to entry and riot has a very simple solution to allow veterans to train new players in a flexible and easy way, but refuse to due to nothing more than stubbornness.