Same age as you and bought a (cheap) gravel bike a few years ago.
Enjoyed it, so after a couple of years I bought a nicer one – Planet X Free Ranger.
Both the above were mainly used for off-road with the odd bit of tarmac in-between – I live in the Scottish Borders, so plenty around.
This year I bought some slicks and put them on a spare set of wheels – lots & lots of battered tarmac here.
Enjoyed it so much I ended up entering and doing a 200k, then 300k Audax while in-between I took it bikepacking across the Highlands (200 miles mainly offroad) and then last month across Southern Scotland (200 miles on tarmac).
I ran 50mm gravel tyres for the first couple of years, now on 42mm gravel and 34mm slicks using two wheelsets, both tubeless.
Now I’m looking to get a Cotic Cascade for the bikepacking, and keep the Free Ranger for tarmac and (fast/local) gravel.
It’s very comfy and I can ride it all day, but it’s still fun just to go out for an hour or two – on either wheelset.