Mine has a usable area of 1367mm x 2710mm. I beefed up the gantry (3mm thick SS tubing, wider strut braces, more strut braces, aluminum struts) and it is pretty rigid.
But I think that a >2m wide gantry would introduce a lot of issues with flex that would be hard to overcome.
I suppose it would depend on what you are cutting (styrofoam would probably be okay at that size, aluminum not so much),and how tight the cutting tolerances need to be for your material…