Respecting your opinion, I still feel like the optimal strategy here is something like this:
1. Trade #3 overall for a pick later in the Top 10, and hopefully garnering a 2022 1st rounder
2. Address the clear skill need on this team with your top #10 pick, as any QB will benefit from that
3. Go into 2021 with Tua as a starter having a full offseason, a more experienced line, a better OC, and a top WR or 2 on board
4. IF it turns out Tua is not the guy after 2021, now you likely have a decent 1st round slot of your own, PLUS the 2022 1st you acquired to grab Tua's replacement.
To me that feels like the best strategy. I could see the case for giving him even more time than that, but respecting some folks want him gone already somehow, let's at least give him a fighting chance and build our roster up. Going after another QB now seems capricious, and still leaves a huge talent need on your roster.