I'm thinking that was the whole point of them changing that rule...you wouldn't give the model a second glance as you would have been swayed by the groundwork...but there are a lot of nuances to Ken's work on the model itself that get lost in the scene...there are a lot of folks here that are great "modelers" who lack scenery building skills and I think the change is to give those folks their due...
You can still do a scene...and yes- entering it into the All-Open might put it against someone's gold medal winner from 10 years ago...but that just means you have to step up your game...the real reason behind the contest is to raise money for the site and the sponsor child...the prizes are just incentive...if they are your only reason for joining, I think maybe you've missed the point...my opinion anyway. Either way...I guess it's up to you to decide what drives you to excel and then you have to call on that to motivate you...