are we sure that non need to invest in Str, Dex?

especially the question is for dex.
since that applies how well you can hit the enemy. and not miss.

that kinda limits the player to select weapons with + to attack ratings. and giving up other benefits. especially early on in the game.
and perhaps even mid game, since who promises you, you have decent enough attack rating?

can someone clear that up to me?

I've never got to 99, I think my highest was 76 or something.
also I wasn't using builds.

there are indeed scenarios where you want to put stat points into dex.
first, if you need to use a specific item with higher dex requirements (bows for example)
second is to rech max chance to block (75%) every point in dex increases the chance. max block is especially of value in hardcore. close to every build is going to use a shield with max block there (there are exceptions) but also in softcore - paladins almost all the time go maxblock.
and the third reason, and i guess many overlook that - it adds ED (enhanced damage) to certain weapon types. (its the same for strength btw)
for example when using bows, amazon bows and crossbows 1% ED is added for every point in dex
this varies for every weapon type. javelins only add 0.5% ED per point in dex.
hope that isnt too confusing and is a little helpful

I'm not super experienced but my understanding is that it is a lot easier to get +Damage and +AR from things like socketables, item affixes, buffs, +skill, etc. But its a lot harder to find sources of +Life. So any sources of Life (i.e putting points in Vit) are very valuable, moreso than points in Str/Dex. Also keep in mind the general mantra of "You can't deal damage if you're dead".

Of course pumping Dex isn't useless if you, as others have said, need to max block, equip an item, or get some more AR because you can't find any on gear while leveling, etc.

Yeah i maybe shouldve added that the concept of pushing damage with mainstats is not really a strategy but more a welcome side-effect. In general your'e better off going as much vit as possible and depending on the build going to reach maxblock.
As for the attack rating issue. The best low budget fix for low AR is the 2-piece set bonus of the Angelic Set (Ring+Amulet) It provides a huge AR bonus, even used on endgame builds - and the set pieces can be found/farmed easily since they already drop in normal difficulty

Also note that the class/build also matters.

Attack rating only matters for increasing the chance your weapon hits the enemy. Spells don't care about AR.

If your character isn't swinging their weapon to do damage, dex and str only matter for gear and block rate, nothing else.

Pre v1.10, there were duels called PallyPK and ZonPK where paladins would

Zeal dual and Amazons would bow dual. In these duels, it was common to put almost zero points into vitality and all your points into Strength for the Paladin and Dex for the zon for maximum damage.

This changed though after V1.10 recalculated how life leach was used. Pre-v1.10, pallyPK duels would see your life bounce from like 15HP to 1500HP in 1 hit given/received, so maximizing your life didn't make sense, rather you wanted maximum damage and AR (dex) to deal the most damage as consistently as possible. Now, it's much more vital that your life is high enough to survive the heavy hits monsters tend to give, giving you enough time to recover the lost life.

Then V1.10 hit, runewords were added, several item stats were changed, several items were added, builds like the elemental druid actually became viable, and changed how the game functioned. It was a HUGE change and drastically changed the way the game was played. Whether it was for the better or worse is hard to say, but hopefully that bit of history might give you some perspective on why you don't see it that much anymore. Gameplay from my perspective has shifted from a mostly PVP focus to a more PVM focus.