This is hardly unexpected news. A company with the name of Wharf Land Investment would not have purchased the airfield if they felt that aviation would continue there for the forseeable future. Promises that it could do so were always meaningless. Land investment companies often use this model, buy on a promise to keep it going, prove that it is uneconomic to maintain 'as is' and propose housing or factory development. Blocking of such proposals are overcome by the 'ratchet effect' of a steady stream of planning applications over a lengthy time period which wear away local resistance and the building permission is eventually obtained.
Proposals of a 'theme park' are just a smokescreen as there would never be enough tourist trade, month in, month out, to make it viable. There will be a vast housing estate, or an 'upmarket' development where the airfield used to be, in about 10 years. Just wait and see. The returns from such an outcome are so high that Wharf Land Investment can afford to wait, they know that they are highly likely to win. The same will happen, eventually, on what is left of the beautiful Hamble airfield, where the owners are playing the waiting game.
It will be a sad day when Sandown is no more, it's always a favourite 'day away' to go there. Maybe there is an IOW resident who might open a private PPR strip. That might be viable, given the low traffic levels.