A big part of the supply shortage (on SFHs at least) in most markets has been driven by the parabolic growth of mortgage forbearances this year. I've seen estimates that in 2019, only about 0.25% of homes were in forbearance but that jumped to almost 10% at its height this year (it's estimated to be just under 7% by the last report I saw). That's a growth rate of 2800% in 1 year.
Essentially, you have a lot of homeowners in distress who are being paid not to sell their houses right now. Most forbearance programs are only active for 12 months (though this could easily get extended), so that would put a lot of homeowners from the first wave of Covid-forbearances up to a decision to sell by around April - May 2021. If that is the case, then you'll likely start seeing supply increasing shortly thereafter and thus prices declining. However, that doesn't mean demand is necessarily going away, so don't start shorting the market yet either.