My question has been clarified, the best option is to go for a modern DSO. Although I have a lot of empathy for "vintage" equipment, it seems to me that in the particular case of old DSOs (2440) their limitations get very stark compared to entry-level DSOs. As I understand it, this is not the case with vintage Hi End analog scope, like the TEK 2465 & 67, perhaps because there are no more products like these these days.
The right conclusion, but for slightly incorrect reasons.
History: compared to the equivalent analogue scopes, early DSOs were boat anchors, nasty to use, had insufficient bandwidth, but could do post-processing. Analogue storage scopes were fast enough, but even nastier to use than DSOs! Hence people preferred faster analogue scopes, and only used digital scopes where their slow single shot captures and post-processing capabilities were important.
Currently: DSOs are at least as good in all respects as analogue scopes but - and it is a big but - there are important use-cases where the purchase price of an analogue scope is significantly lower than that of an equivalent DSO. Those use cases all require recording signals with several hundred MHz bandwidth, especially for digital "signal integrity".
Thus if you are price sensitive, you may need to consider "good" old analogue scopes with >200MHz bandwidth. Such good scopes can also be used for many purposes for which low-end DSOs can be used.
Thus your choice is sound: to retain the good high bandwidth analogue scope (Tek 2465/485), and add the
different benefits available in low-end DSOs.