Although I agree with this and believe that grinding now is way too easy compared to how it used to be, the old ways of grinding are "too hard" for some of the community that hate grinding. The addition of infested tiles fixed that issue but now it's also way too easy for the small minority of players that enjoy plunging hours of time into grinding knowing that they'll get something big out of it. An example of this is farming a shulker of GP. A year ago, it would've taken an hour or two at a GP cave but would sell for 3x the price they do now. Now this takes 10-20 minutes and sells for extremely cheap.
I don't believe there is a real way to "make it more fun" to grind without it taking longer to do and giving a higher reward which eventually people will complain about saying it's too hard and will want an easier way to do it. There needs to be a balance between hard to do as it'll please that small minority, but easy enough for even the people that don't like constantly grinding to do it. In my experience, grinding was fun because I could get a large reward out of it. Sadly, now I just don't get that same enjoyment from grinding as it's so easy to grind.
Infested tiles try to be hard by having red tag or the mobs being a constant nuisance but they just aren't nearly the same as a lesser reward and a longer time, which sounds odd because that sounds bad but that time spent just gave that satisfaction at the end when you knew you'd actually worked and spent time towards this achievement.