Of course that is with XM-Ls, literally nobody uses XM-Ls nowadays, except for chinese super budgetlights meant for the chinese domestic market.

But we also have the answer for today’s emitters.
Take 3pcs of BLF Q8, 400g each that’s 1.2kg mass, same as the X100. (just for info, with batteries this bumps it to 600g total weight, or 1.8kg for 3pcs)
4 x XP-L = 5000 lumens at 1250 lumens each emitter, 3 pcs give 15k lumens.

It’d hit thermal regulation and ramps down at the 3 minute mark.

It’s probably at this level with a 1.2kg (empty weight) light at 15k lumens with similar efficiency.