Creating beta-neutral systems with Robinhood would then be possible.
Well,
The way I approach betting against the market is inverse leveraged ETFs. If you want to bet against S&P 500, ProShares has a 2X inverse offering, and you can probably balance it with 3x leveraged gold JNUG / JDST as they track the market.
Creating beta-neutral systems with Robinhood would then be possible.