We have this "Maximum event length" option under Settings | Video for our 2nd gen battery camera in the Google Home app.
Is your doorbell a 2nd gen Google Nest Doorbell, installed in the Google Home app?
1st gen Google Nest cameras and doorbells are installed in the Google Nest app. 2nd gen Google Nest cameras and doorbells (which began to be available in Sept. 2021) are installed in the Google Home app. (It's confusing to have to deal with 2 apps.)
I was NOT suggesting you have a battery camera. Since your post says you have a "Nest Doorbell (Wired Gen 2)", I was pointing out that our 2nd gen camera--installed in the Google Home app--has a "Maximum event length" parameter under Settings | Video. (I don't have a 2nd gen doorbell, so I couldn't show a doorbell screen shot.)
However, the "Nest Doorbell (Wired Gen 2)" first became available in October 2022. If you installed your doorbell in January 2020, then you probably have a (1st gen) Google Nest Hello Doorbell. (We have 3 of them.) The (1st gen) Google Nest Hello Doorbell is installed in the Google Nest app, and while this 1st gen doorbell also appears in the Google Home app (if you've migrated from a Nest Account to a Google Account), it simply does not have 2nd gen settings like the "Maximum event length" option because its a 1st gen doorbell.
The (1st gen) Google Nest Hello Doorbell has a black face with white sides. The 2nd gen Google Nest Doorbell is larger and comes in several colors and the sides are the same color as the face. See screen captures below.
