"Call of Duty" servers for the 360-era games have been fixed, some with 100k+ players online
Sadly, the servers for many of the titles previous to the 8 generation of consoles were offline for quite some years, leaving only the most recent titles to be playable online. However, due to the whole discussion and on-going arrangements regarding Microsoft acquiring Activision, it seems like one of the involved parties in the merger have fixed the servers, and players wanting to relive their beloved days of getting roasted by kiddos can do so right now.
Titles such as Call of Duty: Modern Warfare (2 & 3, haven't confirmed if 1 works), Black Ops 1 & 2 can be played online back again thanks to the server fixes (with many people have citing it's thanks to Microsoft pushing for a fix to the servers instead of Activision, but it remains to be confirmed). The games can be played on the original Xbox 360, but they can also be played on Xbox One consoles and through the latest Xbox Series consoles as well through their classics service, though some players have been experiencing input delays when playing through the Series consoles.
Almost all of the CoD titles are currently seeing thousands and thousands of players online, with the least amount being around 8k to 10k for titles like Black Ops 2 and Modern Warfare 3, to the incredible number of 70k up to above 100k players online for Modern Warfare 2 and Black Ops 1, respectively.
It's likely that Microsoft is re-enabling these servers ahead of their Activision merger and in preparation of said games appearing on their Game Pass service, but it's all speculation at the moment.
If you have that soft spot for the older CoD titles that the newers ones just cannot match, be sure to jump right back into these titles to relive those great moments from back in the early 2010's right now!
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