But what I find fascinating (understandably) is the vast amount of time discussing multiplayer. If one didn't know Halo, one might think it were only a multiplayer game.

Personally, I don't really play multiplayer at all (any more). I simply don't have the time, nor the amount of friends who also play regularly to connect with over a game like Halo (let alone any who wouldn't mind being held back by my drastic lack of MP skillz).
And my love for Halo has always been campaign.

Understandably, the ongoing active life of a game like Halo has to be in keeping an active community, and the only way to do that is either through hefty creative work with regular new solo content, or rallying around the multiplayer mentality; and it's a lot easier to organize regular events and build up hype when connected with what the community is already doing - competitions, game nights, custom content, live interaction, etc - especially with 24/7 social media. But that necessarily leaves out the solo campaign portion; a fundamental difference in gameplay that's just incompatible with community mentality (save co-op, obv).

If you think about it, Halo has done amazingly well compared to the days of old when games were only solo campaign, and their abillity to last was based solely on replayability. Halo has had so many revisits, rereleases, updates and upgrades, that 343 has indeed kept unique content and experiences available for all play types. The quality of that, well YMMV.

But to be honest, my interest in Halo has been waning over the last few years. Why? Because 98% of everything I see and read about Halo is multiplayer this, competition that, online everything, prizes, people, community... And not that any of that is bad in and of itself per se, but the essence of Halo, to me, is lost in the noise. It's not that campaign has reduced, but everything else has increased.

For me and those like me, my interest in Halo won't wane if there's no new content every month. All we want is amazing content and lore every couple of years to keep that spark of the Halo universe alive. And generally speaking, for campaigns in the Halo universe, that's been the case. But recently it still feels that it's being drowned out by so...many...voices... the noise of crowds and events and gatherings and cheers and prizes and whatnot.

It's sort of like... multiplayer is to campaign what extrovert is to introvert. Or something like that :)

But worse, is when the multiplayer mentality eeks its way into the solo campaign mentality.

In classic Halo, solo gameplay gave birth to the multiplayer environment. Multiple players played within (for the most part) the sandbox of the campaign gameplay, with a few relatively simple MP maps. As the iterations went on, slowly the multiplayer gameplay influenced more campaign decisions; balancing, weapons content, enemies, AI, etc. These days it sometimes feels like it's the campaign that's tacked on to the multiplayer engine...

Map design - is this level good for solo AND multiplayer action?
Weapons - are there equivalents for different races so different game types and variety can still be balanced?
Customization - can we hold back and reward in-game content that can be used in multiplayer and vice versa?

From a solo campaign player perspective - Halo has become a franchise that is being influenced and led by multiplayer mentality. And to me, that's had an enormous impact on my impression and love for the series. Not in a good way (for me, only because I'm not really into the multiplayer). If I'm not alone on this (though I'd wager I'm in the minority at most), then how much has the entire franchise changed in perception since 2001 because of that shift?