This website contains age-restricted materials including nudity and explicit depictions of sexual activity.
By entering, you affirm that you are at least 18 years of age or the age of majority in the jurisdiction you are accessing the website from and you consent to viewing sexually explicit content.
Does that come with app update? I still have normal categories up there:

Google AB tests every tiny detail so you might not see it.
I have 19.03.35 Revanced; may be a regional trial?
I have the official unmodded YouTube app v. 18.46.41.
Anyway, it would probably show up since it’s not a client-side thing. Could be a regional thing. Or just random testing.
Why do you have the official app? I can never go back to normal youtube with all the in your face ads. Soon I’ll stop using pixel phones if Google doesn’t stop forcing me to buy google drive/photos subscription.