So If a ceasefire is broken somewhere down the line (and it probably will) Western NATO countries can no longer turn a blind eye to Russia blatantly violating an agreement that Turkey made with them. Turkey will have a credible cassus belli in Western opinion to respond to new Russian aggression and NATO will have to support a type of no fly zone over Idlib or forever be known as a failed organisation which has no legs to stand on.
Thats already the case tho, NATO= US its not an independent entity and most member states are weak especially those in Scandinavia and Eastern europe. I also give this Alliance at max. 10 years before it dissolves.
Its all about Turkish-US dynamics. Thats the important factor.