FWIW, here is some pricing history on my 2019 M3P. Black, white interior, no FSD, 5,700 miles. Car was $60,990 - $3,750 tax credit.
January 2021 - the highest trade-in offer I could get was $42,500. FSD would only net me $500-$1000 on all the offers. IMO, the depreciation was pretty bad on this trim level.
July - 2021 - the supply chain shortages started to take hold and suddenly Carmax offered $48k, so I took it not knowing at the time how long this would last. If I would have held out a bit longer I could have got in the low $50k range on trade.
IMO, the M3P depreciates a bit more since there is not enough differentiation between the LR to justify the price increase. However, our 2019 SR+ is worth about what we paid for it 3 years later. I know inflation has taken hold but it is really hard to stomach having to pay like $10k+ more for a new SR+. I think I would need to see some sort of meaningful refresh to justify the spend.