I didn't give enough consideration for the whole 0% BIK thing when I bought my M3P outright in 2020. I also thought, silly I know, that the 3/Y wouldn't be an outrageously high volume car. Don't know why I thought that, mainly I think it was because at the time I bought mine.
If I had thought about it properly I would've realised that beginning 3 years after the launch in the UK there would be a constant stream of cars coming to the second hand market, going to auctions, etc. These cars would be sold for whatever trade could get for them, unlike private sales. This means a constant depressive effect on residuals.
0% BIK makes them a complete no-brainer for businesses, therefore it also seems to be a no brainer for a retail customer to go with PCP/leasing as well. The only exception I think to that is if they genuinely think they're going to be buying their "forever car" (for several years at least). Unfortunately there is the issue of the battery warranty only being 8 years, at which point I presume the cars drop off a cliff again depreciation wise, and become deeply concerning to continue to run.