Valve let bots infest and ruin TF2 servers for 8 (eight) years straight before doing anything. There's no way they'd add anything like that to TF2 within one year.
Of course not. They’d just add it to VAC and make it an opt-in flag for all Steam games. And then check that box for TF2 et al., because one click in a metadata editor to lock out 99.999% of software cheaters is a no-brainer for any multiplayer game — including their own! And as a bonus, that’s an upsell driver for sealed-capable hardware like the upcoming Steam console, when people find out that their Win10 PCs can’t access their inventories next year and it’s either Windows 11 or Steam Linux. Mod it all you want for local play, then dual-boot to a competition-grade sealed OS to join lobbies? Hard to see how they’d turn that opportunity down.