It's the expandable EAR yellow foam plugs for me.
Been using them on the motorbike for years, regularly use them for sleeping on windy nights.
Cheap as chips and they do the best job, IMO.
Note this comment from one of the links you sent.
If you're looking for sleeping ear plugs but are afraid of completely blocking out the outside world, these Alpine earplugs are the solution. They reduce surrounding noises like traffic, neighbours or a partner's snoring so that you can get the sleep you need. However, the sound of your alarm clock in the morning, a telephone ringing or a voice trying to wake you can still be heard. Best of all, these are reusable earplugs, so one pair can last a long time with proper care.
Sorry, but the above statement just seem completely contradictory, to me.
You can't hear snoring/traffic/neighbours, but you can hear a phone/clock/voice?
Eh?
How does that work then?
Pish and twaddle.