I've had a couple of experiences recently which have made me wonder if it's becoming the norm just not to reply to messages or if it's just me.
The first time, a friend had asked if they could pop round as they were in the area, and I only saw the message a few hours later. I messaged back to say sorry, I'd been distracted that day as I'd found fraud on my bank account and had been busy sorting it out. No reply.
Then today, I messaged a group to let them know I couldn't make a planned gathering as I've got a migraine. No reply from anyone in the group.
I wouldn't care about a reply in every situation, but in these cases, were the tables turned, I feel I would definitely have said something like 'oh that's awful, did you get it sorted?' or 'that's a shame, hope you feel better soon'
And in case anybody asks if it's perhaps because I'm the kind of person who's always making excuses, I don't think I am, but I do know a few people who always pull out of things, and even if in my head I'm thinking 'here we go again', I always make a point of sending a polite reply. I just think it's... well... polite?