A social dog is much more than not being aggressive, or happily running to every dog seen.
A social dog is able to read cues from other dogs and regulate themselves accordingly as well as being able to offer cues to regulate the way other dogs interact with them.
While these skills can be learned through interactions with other dogs, expecting to just “work it out” sets them both/all up to fail.
If a dog is repeatedly put in situations were their requests for space are ignored they start to predict other dogs are not safe to interact with. They can try to shout louder by using teeth, growls, or even escalating to biting.
Or if they are overwhelmed and they are unable to offer cut off cues they find themselves stuck in play, especially games of chase that they do not enjoy but have no ability to stop. This puts them in danger.
Conversely, if a young eager dog is reinforced by play with a dog who was requesting a break or simply running scared, they learn that those cues mean nothing and will ‘bully’ dogs into play. This sets them up to fail when they struggle to make friends due to rude behaviour.
Social skills can be improved but not by just exposure to groups of dogs. They need to learn what TO DO with appropriately matched dogs, supervision and reinforcement for correct choices. This can be a very slow process and is best guided by a professional force free trainer.
Things to watch for to signal good play skills are loose, relaxed and bouncy body language. Regular breaks in which both dogs pause and then choose to reengage. Taking turns being the dog chasing, on top, etc. A larger or more confident dog should handicap them selves in play by laying down or making themselves seem smaller and less threatening to encourage the other dog play will be safe.
Remember that dogs are allowed to have preferences, they may not want to play with every dog they meet and that is OK. If you are ever unsure preform a Consent Test. A consent test means to separate the play and release the dog that you are not sure was enjoying the play first, if they choose to engage with the other dog try letting the play continue. But if they avoid the other dog they were likely not choosing to be involved in the play and you should move on.
If you would like to understand your dogs signals more clearly book a consult to translate their language for you and give you a better lens to understand what they are saying.