Minor point, but I think the scale of such things is often not actually well presented. Because I cannot see a world where a +8 is "decent" if we are going to take the scaling of normal people seriously.
Let us say you have no training. Can you get a +8 with pure "natural talent" via Ability Scores? No. Absolutely not.
Okay, let us say you are an average person (+0 or +1), and you have training. Can you get a +8 that way? No. If you have a +1 and you are essentially a demi-god (level 17 to 20 character) you can get a +7.
Okay, what if you are an average person (+0 or +1) and you were a climbing expert. THEN could you hit a +8? Yes, by "level 9" you could get a +8 by doubling your +4 prof mod. And what general tier of skill do we consider that level? This is the top end of "Heroes of the Realm" and moving into "Masters of the Realm" ie You are somewhere between one of the top people in the country to the top in the world.
We can get it earlier of course. You just have to be massively innately talented AND a trained master in the field. And I do mean massively. The last time we really had full descriptions of what the Ability Scores meant I believe was 2e. And they listed Intelligence. A 12 was "Very Intelligent", 14 was "Highly Intelligent", 16 was "Exceptionally Intelligent" and 18 was "Genius". To hit a +8 before level 5 you need to be a trained master in the field AND have a "genius" level score.
Which... is not how I would define "decent" which means "adequate"