Unfortunately, you don't hear muscular people live to very old age. I will just focus on eating well, doing cardio & stretching exercise, and spending my time on my hobbies.
You refer to bodybuilders who have used and abused steroids and other PEDs. As for the rest of your post, fine. But you might want to have a look at this 4-minute video:
Unlike some ham handed roid users, I am comfortably training at age 64+. Because I did a have a 1,050 3 lift total as a 148 pounder back in the day. I've accomplished something and don't need to prove it now.
Zero gear. 10-12 reps. Sets to failure. None of this PAB crap you ppl are doing. Scandi-giants of the world unite! https://www.elitetrader.com/et/threads/me-at-60-y-o-and-me-at-70-y-o.379888/#post-5983106
I'm not a powerlifting guy, so I had to look it up. DTB2's numbers seem to be quite good: https://strengthlevel.com/powerlifting-standards/lb#standardsMale
As I had mentioned, those were my changes as well, except I don't know what "more core focused" means. I do some ab work, as always, but I would think that most exercises, especially compounds, contribute to "core" work.