For the sake of the generations that come after us, we really should not dump valuable material into space. I somehow doubt the electronics in space would be recovered and recycled properly.
Also, burning plastic waste in a power plant at least liberates the energy for use. One can argue it's just fossil fuels that spent time doing something useful before it became energy.
Taking rare elements to space only for it to stay up there or burn up in the atmosphere removes it from this whole equation.
I don’t know where "here" is for you, but even a country like Germany only manages to recycle 38% of plastics overall, and a huge portion of that is plastic bottles - the lowest-hanging fruits of the recycling tree.
And all the while, every day millions of single-use vapes are sold and discarded, each of which containing a microcomputer and rechargeable battery. Recycling is a lie.