You are probably right about differences in experience.
We base things in our life on our experiences.
If one person has negative experience of seeing hand holding, a quick kiss, arms around the other, “I love you”, then that person may associate seeing those forms of express as negative. Those relationship forms of expression can trigger negative thoughts, feelings, memories.
If one person has positive experience of seeing the same thing. When they see it again or discuss it, they have positive thoughts, feelings, memories.
If one person has the belief that such behavior can only be part of a “marriage that is just great top to bottom”, then a judgement has been placed on “when this can happen.” With such a high level of “when it can happen”, that level will never be reached and maybe to them “no one has meet the level, so no one should be doing this.”
How our parents and other older relatives (aunts, uncles, grandparents) saw holding hands or a kiss at Thanksgiving dinner, etc. will affect us as well.
What we heard our parents say about others who kissed or hugged will affect us as well. **
Why** our parents held their belief on holding hands and sharing a kiss in front of others affects us as well, even if they never told us why they held that belief.
If we only see dysfunctional people at family gatherings as the ones holding hands or wrapping an arm around their spouse - our idea of those forms of affection are connected to dysfunctional people.
If the single people in our life were not upset seeing couples hold hands, we may hold the same idea - hand holding is acceptable in front of single people.
If our single friends are more likely to have unhealthy feelings that they are “left out”, “alone”, “a 5th wheel” - then we might adopt this attitude as well - single people can not see couples holding hands.
I grew up seeing people I loved (parents, aunts/uncles, grandparents) share a kiss at Thanksgiving while going about the busyness of the gathering. I heard the “fussing about the way you cut the turkey” while at the same time saw the working together of the spouses and the happiness between them. The laughter, the loudness, the happiness, the fussing over who would sit where - the non-perfect spouses and families - the love that was there - shapes how I feel positive about couples sharing a kiss, etc.
As cousins and siblings and myself grew up, we expressed those same kisses and hand holding with our spouses at Thanksgiving gatherings - lots of laughter, happiness, fussing, love.
I see the same when I am with friends today, friends who share a kiss with their spouse and who might fuss to their spouse about a detail that needs to be tended too. Yet, what I see is love shared between these spouses. Their happiness, their closeness transcends throughout their home. Its a good home to visit.