For SSAs: yes. For everything else: it depends "but...".
Now an individual affix like +30 of X stat is not going to have much of an impact but it piles up meaning that so called "God Units" (SSA + Guardian Soul + Absolute Glare + Veteran's Resolve V + Crack V + Aether Factor + Mana Reverie + Mark X / Grand Y) will actually have a rather noticeable impact on your performance as 3 of them will give you about 20% more attack and 30% more defense as well as 50% more HP. You also need to hit certain thresholds for various effects to activate / become more potent such as the bonus effects from Live / Photon V Adaptation.
The biggest issue here however is the storage space as you need to collect a lot of fodder pieces if you want to make this stuff yourself and you can't buy inventory / storage space extensions from other players either because SEGA essentially took the "screw you that's why" approach here.
The absence of add ability capsules, especially for the Mark abilities (which I wish they would have added to the badge exchanges like they did with all the summoner stuff), is another issue here.