The 8.5 months quoted on the processing times pages doesn't mean all cases will be processed in 8.5 months. I explain what it means in this post: Understanding USCIS I-130 processing times - IR-1 / CR-1 Spouse Visa Case Filing and Progress Reports - VisaJourney
After considering the processing times, I think the best metric is what is reported on the USCIS Historical Processing Times page. Currently, for I-130 for Immediate Relatives, the median time for approval across all service centers is 9.5 months (for Fiscal Year 2022). I like this metric because USCIS shifts cases around to balance the workload, and this will capture that. It also uses the "processing time" methodology rather than the "cycle time" methodology, which I think is better (and explained in my linked post).
I think the way they present the processing time data isn't great and leaves more questions than answers. Like you, I am frustrated at how long it takes, but the backlog is insane. As of Dec 31, 2021, there were 308,775 pending IR1/CR1 cases across all service centers. From Oct 1-Dec 31, 2021, they processed 61,861 cases (about 20,620 per month). So even if they completely stopped accepting new cases, it would take them 15-months to process the cases they currently have. And this is only for IR1/CR1. It is considerably more when you add the other categories.
It is even worse for those who are applying today because the backlog is the highest it has been since at least Dec 2018 (and probably longer but I don't track it before 2018). For perspective, there were 223,249 pending cases on Dec 31, 2018 (which is 32% lower than Dec 31, 2021). In other words, the backlog has grown by 32% over 3 years.
Luckily the Biden administration is giving USCIS more funding and committed to reducing the backlog. We would be in a much worse situation if Trump got 4 more years, or thinking ahead, if a different conservative administration gets elected in 2024. Because after the IR-1 process, most beneficiaries will apply for citizenship, which is also extremely backlogged. Elections have consequences and at least for me, I will vote for candidates who are committed to fixing the US immigration system, because it is broken. We deserve better.