How so? I have never, ever, in 2000 hours of playing, formed a federation.
Wait... hold on... I'm sorry. I did it once for an achievement. But I don't think traditions even existed at that time.
Any tradition you aren't using is a waste.
There are very, very few traditions that every empire does not gain a benefit from. Federation is the rare exception. Let's do a rundown per category:
Expansion: The only questionable one is -10% starbase influence cost, as if you take this outside of the early game, you're probably not going to use it or, in the rare case where you do build an outpost, the cost savings aren't felt. That said, every empire could conceivably use it if they chose Expansion early.
Domination: Everything is used by everyone.
Prosperity: Everything is used by everyone.
Harmony/Synchronicity: Everything is used by everyone.
Supremacy: Everything is used is used by everyone. Yes, even pacifists gain benefits, as they still need to have some navy.
Discovery: Like Expansion, only one questionable one that is only really beneficial in the early game (33% survey speed + disengage chance), but everyone can still conceivably use it.
Diplomacy/Adaptability/Versatility: 10% Habitability stops being useful by the time you get to mid-game, but it is relevant longer than those talked of in Expansion and Discovery, and it still does a little tiny bit while waiting for a colonized planet to teraform. Completely negated by those going for synthetic ascension, but that's mid-late game. The only other questionable one is the -33% cost reduction for resettlement, as that is something a player can choose to never engage in. Whether it's wise is a separate question, but for those who don't want to touch it, it's another Federation.
Federation is the only one that is flat out useless 99.5% of the time from my play experience. Nothing comes close.