I think that probably has more to do with how recently you were in REM sleep (which is when most dreams occur). If you have the sensation of waking up from a dream, whether you remember it or not, you likely woke up from REM sleep. If you don't think you dreamt at all, then perhaps you just were in REM sleep much earlier during your sleep.

Do you have any evidence for that. It's very likely you had dreams with both experiences but just didn't realise it.

It seems more likely that the brain has some kind of retention filter on dreams to try to sort the random useless signals from, for example when you deduce the structure of the benzene molecule. Probably all humans dream every night, unless there's some major issue with sleep, but only dreams passing the filter are remembered. Those on the threshold are "remembered as existing" but not the content.