Expecting someone to contribute day1 is bad mentality, proof of bad management.
Bad CTOs and Tech Leads can't understand that they hold knowledge of years building the code estate (while often skipping documenting it), which is difficult for newcomers to accuire.
Just setting up the machine can take 2 weeks.
And they are in their own echo-chamber, thinking every choice they made is the right one and must be used everywhere.
"What? you never used tool A? It's what we use everywhere". Well good for you! I used tool B, C, Z, X, A7, and forgot most of them. Don't give me these looks!
And of course, working in such conditions you can't improve. They exclude you from discussions, give bad looks and comments, and completely erode your confidence.
You might not be the best, but they are definitely worse.