I’ve earned over 500k MR YTD, mostly from SUBs, organic spend, Amex Offers, and just a few cross-supportals — so yeah, totally possible.
Amex has so many different MR earning cards, and their SUBs can be extremely generous if you pay attention to applying for only the highest and best offers. In 2-Player mode, you can earn a lot of additional MR from supportal bonuses by cross-supporting each other to new cards. New cards mean lots of spend, so hopefully that’ll keep the pop ups at bay. If you want to stick to biz cards, there’s the Biz Green (25k MR SUB via supportal, $3k MSR, 3 months, $0 AF first year), Biz Gold (tiered 75k MR SUB via supportal, $10k MSR, 3 months, $295 AF not waived), the call-in Biz Plat (100k MR SUB, but no supportal, $10k MSR, 3 months, $595 AF not waived), and the BBP (15k MR via supportal, $5k MSR, 3 months, $0 AF). I believe you (or DH) recently opened a BBP — that card is currently generating supportals worth 15k MR (max 55k MR/year) + whatever SUB the other player gets from the card they’re applying for. The catch is many of Amex’s cards with big SUBs have AFs, so you need to be able to justify the SUB, credits and benefits, and your planned redemption (e.g., your $11k seats) vs. the cost of the AFs; and big MSRs, and MSing an Amex MSR is a bit more difficult and probably requires you to, um, increase your grocery spend. And unlike URs, you can’t combine MR points into one account, so DH would have his stash and you would have your stash.