They can’t do that now. I play for about 2 years regularly and I’m already a lost cause for being expected to have wild cards; new players from this point would be even worse off; i.e. in order to support Wild they’d have to drastically give cards to people for free.
But the entire subject is moot since it has a systemic balancing issue; they already struggle to balance Standard only and Wild “balancing” is usually a couple of blatant bans that don’t do much; maybe they should start considering developing good simulation.