I really do want a Mayday movie but Sony would definitely fuck it up for me. I don't even want to think about how badly they'd butcher her personality or what kind of ugly lesbo they'd cast.
Other that, fpbp is right, it's too convouluted or maybe complicated is more the word. A lot of every story Mayday has been in relies on knowledge of the clone saga and a whole bunch of other obscure 90's Spidey shit that has never made it to film. Normalfags would definitely not respond well to it. Apart from that, it also requires and I mean requires the Fantastic 4 and some other properties that they likely don't have access to.
If they have to change a ton of shit, I really don't want it to happen at all. 2099 would definitely be the better sell and would way easier to pull off.