The metagame keeps getting more "varied" with PK remaining at the top due to its representation however it's not as powerful as former tier 1 decks, so many different archetypes are able to get results.
Despite the variety, there are similar flavors. Mekk-Knights, Hero, Dark Magician, Solfachord use their engine to draw into backrow to control the game and use big monsters to beat over their opponent.
PK and Resonator have a consistency skill to search in-engine disruption, bosses with high attack and destruction/removal effects and tech space for access to limit 3s.
Salamangreat -with Code-Talker skill/engine- stands apart as the sole consistent almost all-engine deck.
Infernoids, D/D/D, Mekk-Talker (the superior Mekk-Knight version in my opinion) are the high-roll & high-ceiling decks that in theory have tiered status but don't see much (or any) representation in community tournaments.
Tier 1
In my opinion the main reason Phantom Knights are in Tier 1 is its large representation in most competitive tournaments, but its power-level when compared to other decks is not insurmountable (It's more of a coin-flip deck to me, to be honest). It's still going to win and see representation in top cut for sure, but I expect its dominance to degrade over time.
Phantom Knights are still Tier 1, but in my opinion I could see this drop at any time. It has the consistency but its power leaves a lot to be desired, at least in my experience.
Tier 2
Mekk-Knights are back at Tier 2, proving to be one of the better options in a PK/DDD/Infernoid format and one of the most annoying decks to play against. It still misses the power loss from losing the Limit 3 traps, which makes the matchups against Tier 3 decks like Salamangreat, HEROs, and Timelords much more difficult. The deck's consistency issues have not changed much either, but overall the deck is powerful enough to shine above the Tier 3 decks for the time being.
Mekk-Knights are back in Tier Two, primarily because of representation rather than power (like Phantom Knights). It should bat Phantom Knights more often than it does, since most builds play around six flipdown cards and sometimes even main Loading... (which of course hinders its performance against other decks).
Mekk-knights are a well-performing deck when it comes to stats, but there is hesitancy due to the lack of Limit-3 cards. In my opinion, however, it's the best deck in the current meta.