Both my 2180 with a Weber VZ 15 style cam and my 1835 with a Weber VZ 15 style cam are 20 years old. Both used Weber lifters which Weber ground to thier specs. The 1835 is still together so I have not inspected the cam and lifter but like the 2180 it hardly ever needed the valves adjusted. The VZ 30 stlye cam was perfect in 2008 when I pulled it out to rebush the lifters, rebuild the heads and replace the pistons and liners. The lifters were dished but not damaged. For sentimental reasons I saved the cam and replaced the cam and lifters with Web cams version of Webers cam and Web lifters. I used Brad Penn oil and the lifters and cam went bad in about 2000 miles. I replaced it with another Web cam (same VZ 30 style cam) and Udo Becker tool steel lifters I have another 18,000 miles on it with no problem.
Your lifter bores wore out and let the lifters wobble. Also most oil does not contain enough ZDDP which retards lifter wear. You take chinese lifters, questionable oil and worn lifter bores and it becomes a recipe for failure. Ones right foot can also have a lot to do with it.

Using a W or FK series can is less stressful on the components but not as fun.