Now This Is What I Call A Stuffed Master Global Album

I like that the Minkus Vol 1 goes to 1952. A lot of interesting material between 1940 and 1952.

Agreed. (Minkus specialty albums were also quite nice.)

Of course, I can never come up with a cut-off date for my worldwide collecting:

1940 is way too early: WW2 and the aftermath are incredibly interesting.

The 1950s have lots of great line-engraved sets, as well as the ramping up of the Cold War -- North Vietnam, DPRK, etc. start in this era and their early issues are challenging.

In the 1960s you get decolonization en masse; much of the independent Africa from this time is awesome. There are some legit rarities even late in the decade, like the Independent Anguilla issue. You have the first self adhesive stamps, and of course every stamp Bhutan issued was a laff.

1970s is pretty much the start of wide-range topical issues as we know them today. Some issues generally despised at the time/and mostly today (UAE, Equatorial Guinea) were produced in low quantities and completing them is near impossible. New British Commonwealth watermark varieties also run through the decade, though these modern watermarks are difficult to see.

The 1980s and 1990s ramp up the issue quantities and face value seriously, but you have the decline and breakup of the Soviet Union, and many countries stopped providing all new issues to the philatelic market somewhere in this period, leading to some very difficult locally issued stamps. You also have the thousands of overprints and surcharges from Guyana.

After 2000, the number of issues and face value get ridiculous for WW, and you have exponentially more self-adhesives as well, but there are still a lot of great stamps every year. You have some new nations like East Timor and Kosovo too.

I prefer postally used from the modern periods, just because picking up complete or near-complete mint collections is easy for most countries -- but I don't think there's any era I "don't" collect.