With a hearty 25 years of Magic under our belts now, we've seen many different deck archetypes come and go. Some archetypes are more persistent than others and undergo significant evolution over the years and formats they see. Some are anchored by particular cards, while others are more fluid.
Something like Affinity, for example, has changed a lot over the years, largely around what worked with Arcbound Ravager originally, but also what works with it now in the context of the format it's trying to eat artifacts in. When Arcbound Ravager was first printed fourteen years ago, it was best of friends with Frogmite and Myr Enforcer, but these days is more often seen getting along with a Walking Ballista and a Steel Overseer.
In Modern, Ravager, Ballista, and Overseer are most likely to be seen battling alongside Hangarback Walker and Arcbound Worker to try and develop threats quickly and efficiently, while in Legacy you'd see them teaming up with Lodestone Golem and Phyrexian Revoker to better disrupt the absurd things their opponents might be trying to pull off.
Their land bases are even more diverse. In Modern, Affinity wishes it could rely on the artifact lands (Seat of the Synod etc.) originally printed in Mirrodin, but most of them are sitting in time out on the banned list, leaving them access to only Darksteel Citadel. In Legacy, where the artifact lands are perfectly legal, they're not even good enough, overshadowed by the availability of City of Traitors and Ancient Tomb. Regardless of which format you're in, though, they're all capable of summoning the ever-present Arcbound Ravager.
Another card that's seen extensive play across a myriad of formats is Snapcaster Mage. Relatively young as far as Magic goes, Snapcaster joined the fray in 2011 with the release of Innistrad and was immediately recognized as an exceptionally powerful card capable going in a variety of decks, as long as they were both blue and had a number of spells. I'm sure it's no surprise to you, dear reader, to find that both Modern and Legacy are formats rife with decks that are both blue and include spells!
Legacy is practically infamous as a format in which you are able to play both Brainstorm and Force of Will, both of which are ideal targets for Snapcaster Mage, but in Modern, Snapcaster doesn't get to flashback anything nearly as powerful, usually targeting things like Lightning Bolt, Cryptic Command, Path to Exile, and Thoughtseize. Snapcaster is instead the glue that binds both controlling and more proactive blue strategies together, giving pilots the flexibility to adjust their game plans on the fly, and making it one of the most popular playstyles for more experienced players.
And in complete contrast, some players just want to see their opponents BURN, in both Games 1 and 2, and preferably with no option for a Game 3. Aggressive red decks have been setting the clock on metagames since the dawn of Magic. They are not so much concerned with what your game plan is, so much as seeing your life totally get to zero as quickly as possible, and as such, the onus is on everyone else to figure out how they're going to contend with that.
Unlike other archetypes that have stood the test of time, one of the only truly core cards to the aggressive red archetype is the most basic of Mountains. Because of the direct nature of the strategy, there is some redundancy in the tools that it can use to see things through. In older formats, aggressive red decks have access to things like Lightning Bolt and Monastery Swiftspear, while players in Standard may have to resort to things like Lightning Strike and literally any aggressive red creature you can imagine. What is consistent is the core ideal of the deck. If they have someone sitting across from them, light 'em up!
But who can say how much of this will be true ten years from now, or 25? It'll certainly be exciting to see how these archetypes and strategies develop (or don't!) in the coming years.