So in Smite there is a Hero called Nuwa. I play almost exclusively Nuwa. Nuwa is a supportish mage with a karthus like ult. However they have a very interesting passive where after landing 5 aa's their next one binds. This is harder in Smite since AA's are skillshots, however that also makes it much more fun and challenging, it becomes an actual game of skill to hit those 5 aa's and then have to land the last one.
As such I build AS Nuwa. It is fun, I enjoy it. However while there are enough AS items that she is allowed to buy to make this work she can't buy any items that increase her AD. You can get things similar to nashors and the like but if I wanted to go for an AD AS with maybe a bit of lifesteal thrown in I wouldn't be able to. All I can do is go AP AS. It isn't a matter of the items not being good on her, it is a matter of you literally cannot buy anything outside of the mage items.
LoL is different. Outside of a few items that can't be bought due to mechanical restrictions (melee/ranged only things like Rav and Runaans) any champ can buy any item and build in any way. Yes Vlad realistically had to buy WotA to function in his desired role, but that didn't mean you couldn't say screw that and build him as a bot lane crit marksman. Smite directly limits the items you are allowed to buy, cutting down on diversity. You could never play AD Nuwa for example, it just isn't possible because you can't buy those items. That is the reason I greatly prefer LoL itemization.
Champs that require a certain item to function like Vlad + WotA is a different discussion though.