Even without covid, the change to EUV is a massive bottleneck. You see , there is but one company in the entire world who is making the EUV machines, ASML in the Netherlands. EUV was on the "edge" of roadmaps since, I dunno, mid-90s or something. ASML persevered and now reaping the rewards. EUV fabs need a ton of capital and investing this much without good institutional knowledge in chipmaking is too risky. And TSMC and ASML had a very good relationship for a very, very long time including TSMC buying 5% of ASML in 2012. So a very very long history culminated in TSMC being the sole top dog in the industry. Intel tried to make chips with parts similarly small without EUV and it took them an awfully long time to ramp it up -- it was supposed to ship in 2015 https://www.techspot.com/news/48577-intel-rd-envisions-10nm-... and the first desktop processors on this process shipped like two months ago, barely making 2021.
So whether automakers could use a 7nm fab is a theoretical question -- there is but one 7nm fab, the one at TSMC and they already sold every wafer they can start. They would be able to sell more if they could start more but there are only so many EUV machines ASML can make so there are only so many wafers TSMC can make. All the gaming consoles? yeah, that's 7nm chips. With AMD and Apple moving to the next line, there'll be some capacity freeing up but the demand is still very, very strong.
OP asked whether automakers could use N7. I answered. Also, in theory, if there would be ample N7 capacity, nuts or not nuts, there's no theoretical problem with it and you could get a real metric shit ton of STM32 out of a single wafer using N7.
So whether automakers could use a 7nm fab is a theoretical question -- there is but one 7nm fab, the one at TSMC and they already sold every wafer they can start. They would be able to sell more if they could start more but there are only so many EUV machines ASML can make so there are only so many wafers TSMC can make. All the gaming consoles? yeah, that's 7nm chips. With AMD and Apple moving to the next line, there'll be some capacity freeing up but the demand is still very, very strong.
Also, another effect I do not see here is the container disruption. Read https://www.vox.com/recode/22832884/shipping-containers-amaz...