This isn't something that will fail overnight, so don't freak out, but the thread engagement is meager, usually no more than two turns, it should be corrected. Additionally, the whole assembly is retained by a pretty small nut, also with only three or four threads. A proper seacock engages the thru hull by 8-10 threads. This is an incredibly and frustratingly common marine industry and DIY error, I still see new boats being built with this arrangement. It should be corrected.
Unfortunately, without hauling the boat, there isn't really a fix. The right way to do it., step by step, is shown here https://stevedmarineconsulting.com/wp-content/uploads/2020/12/TaskSheet187-Seacocks-FINAL.pdf
You can reuse the thru hull and then get a proper flanged seacock like this https://www.groco.net/products/valves-seacocks/flanged-valves/bv-series The thru hull needs to be trimmed to the right length but you then have a very durable, compliant installation.
You could use one of Groco's flange adapters, https://www.groco.net/products/valves-seacocks/flanged-valves/ibvf-flange-adaptor you'd get to reuse the thru hull and the valve, but honestly I don't care for these, they add another joint, they offer no advantage what so ever other than compatible threads, I don't know why Groco even came up with this. I'd just use the right seacock.
If the yard selected these parts you have a good case to go back to them and say it's incorrect, Groco would not approve (and it's not ABYC compliant). You could share the Task Sheet.
What amazes me is who could possibly condone attaching threaded components with mismatched threads? It's like using a fine thread nut and coarse thread bolt. And yet, as noted above, I see this far too often.
