Discussion Marriage and sex and adventure

I don’t know how many people will read this But I still wanna ask.. so I am seeing my husband using reddit since long.. all kind of posts be it dirty or be it intellectual discussion.. we are married for 3 years.. before we used to have sex every now and then but for few months or maybe since an year it’s reduced .. it was first once a week or twice a week then 15days then once a month.. so it’s reduced a lot now. Suddenly before few weeks he asked me for couple swap thing. I believe he must have seen people doing it and posting it in Reddit.. I like this kind of adventures too.. but I wanna know how it works! Is it good for a marriage or it is bad? Does this hamper your marriage or it brings back the adventure between two people?