This is the National Planning Policy Framework. It sets out the framework under which local planners should operate. It replaces a lot of Planning Policy Guidance documents, not always in a way that benefits residents over developers. But there’s one thing it does agree on with one of its predecessors, PPG17, and that’s how the provision of playing fields should look. From para 74:

Existing open space, sports and recreational buildings and land, including playing fields, should not be built on unless:

• an assessment has been undertaken which has clearly shown the open space, buildings or land to be surplus to requirements; or
• the loss resulting from the proposed development would be replaced by equivalent or better provision in terms of quantity and quality in a suitable location; or
• the development is for alternative sports and recreational provision, the needs for which clearly outweigh the loss.

Let’s take these one by one.

“an assessment has been undertaken which has clearly shown the open space, buildings or land to be surplus to requirements”

No such assessment has been undertaken. Not one we can find, anyway.

“the loss resulting from the proposed development would be replaced by equivalent or better provision in terms of quantity and quality in a suitable location”

Leeds City Council has been remiss in the planning of provision of “new” playing fields at Whinmoor Grange: they aren’t accessible – at least not to any built up areas that exist now. Here’s a set of pedestrian isochrones, produced to provide planning permission for the houses adjacent to the fields at the south. They clearly show that it’s over half an hour’s walk to the proposed successor amenity. Assuming, that is, that you think that playing your football next to a cemetery is a superior experience to playing it next to a 17th century listed building that also happens to house the Rugby Football League.

the development is for alternative sports and recreational provision, the needs for which clearly outweigh the loss.

The proposed development is not for sports or recreational provision – it simply removes most of the fields.

LCC think this should be used for housing. They haven’t asked anyone about this; they’ve simply changed the designation of the land from “Business Park” to “Housing” in line with national policy changes. Never mind whether anyone’s made plans for their entire lives based around the supposition that this area would be busy in the day but quieter for children to play in the evenings; no, it’s just been changed, with (as far as we can ascretain) little to no consultation.