Now, I'd have to say no. I read maybe one book a year. ( I "could" read hundreds, but in the end, I don't) I could buy the physical book, which I prefer, and 7 or so others and keep them, instead of a virtual library. Or get them from my public library. Or from archive.org.
The only advantage was the unlimited library and the auto-update of books from revision to revision. But your question has caused me to cancel the subscription.
If you can get it from library or university, I'd say it is -- but not unless you read a lot of books per year.
I can’t say whether it is worth the subscription fee. I have got my employer to cover for my subscription for the last 2 years, but not sure if I will be willing to pay it out of my pocket.
My local library has a deal with them: connect to the library's website, enter your card number, and get bounced through a proxy to O'Reilly's site to read any content.
Perhaps check if your local library system as the same deal.
Since you do have access, could you maybe share if you think it's worth paying for?
It has been handy for a few things, but given the finite hours in a day/week I tend to not read tech stuff in my off-hours, so haven't used it much in general. Most recently used it for some Postgres stuff and IPv6:
* https://www.oreilly.com/library/view/ipv6-address-planning/9...