Think of transmitting power using a lightbulb and a solar panel. The tesla method was beaming its power in all directions, like a lightbulb, so a solar panel placed elsewhere would only be catching a tiny amount of the transmitted power. Very inefficient. So instead, we use something more like a laser- we get a collumnated beam of energy we can send straight to our panel, which is much less wasteful. Of course, actually using a laser and a solar panel aren’t ideal because they’re both pretty inefficient, so we use a lower frequency we can work with more efficiently, like microwaves. We still incur some heavy losses doing this though. This also explains why we don’t beam power away from areas with plentiful renewables, line losses in normal grids makes exporting energy to somewhere across the globe infeasible, and the costs of enough space infrastructure to beam power around are way higher than the low return you’d be able to get by converting energy to microwaves and back twice. In fact, the inefficiencies from this process are bad enough that it already makes space based solar economically challenging. Maybe when starship becomes operational and launch costs drop another order of magnitude, it’ll be viable, but until then I think our photovoltiacs are better placed on the ground.