A treatment isn't an alternative to vaccination. Millions of people have been vaccinated so we know it's safe, while tons of people have died from covid so we know it's not safe.
This study appears to show that there is a treatment that’s ~90% effective at reducing deaths.
The vaccines are not shown to be (may be) safe outside of a brief few month window (for specific classes of people). These are a new class of vaccine and there appears to be significant risk based on the cdc data (VAERS).
To be clear none of the vaccines really completed a standard phase 2 or 3 trial. It had an abridged or expedited version that skipped things like pregnant women, etc. the vaccine is also not 100% effective, which is important as it’s a “leaky” vaccine. Meaning, we’re going to see lots of variants that get around our protection from the vaccine. That’s why treatments are important.
It’s also possible we see genetic defects 2-3 years from now or an increase in cancer. We really have no idea.
> Millions of people have been vaccinated so we know it's safe
In those millions we are missing the number of people that get seriously harmed, and killed due to getting the vaccine. So we do not know it is 100% safe, we only know that it is mostly safe, which is not good enough to be cheery and happy about it.