You can lower TDS without spending $500. Install a sediment pre-filter (that cheap, white cartridge) before your main tap. It catches big particles, but it won’t touch dissolved solids. Still, it stops your main filter from clogging.
After that, buy a countertop distiller or a small RO unit. They cost about the same as a few months of fancy bottled water. Yes, you’ll hear that humming noise. Yes, you’ll feel superior. Your taste buds will thank you.