There are big changes in the quality of the components used in the latest 2465B etc models, compared to ones made say 15 years earlier.
The last ones were made 1994-1996 or so.
I have been in electronics design and production since 1978 and things had really improved in the 1990s, with really good quality SMT components, including the miniature electrolytics. I have many thousands of products out there with the same components and most of them are still working. The actual MTBF numbers we are seeing are of the order of 500+ years. With SMT, things improved a lot because the components had to withstand crazy soldering temperatures, so the chemicals had to be improved.
When I read reports of the WIMA polyester film caps needing to be changed, I simply do not believe them. I have used those caps since the 1970s (they were the primary ways of getting a cap in the say 1000pF to 1uF range; nowadays one would use ceramics if possible) and never saw one fail.
Old electrolytics do dry up and fail, certainly, and in these scopes these will be found mostly in the power areas. But again the most recent scopes should be ok for many more years.
OTOH the very recent, say 1995, examples go for a lot more money. I have just bought a 2465DVS for GBP 250 and it is fully working and a superb scope, but that one will be from c. 1985.