Don't freak out about Ninja Tabis.

I can feel it coming.

"Everyone's building Ninja Tabis! They're OP, please nerf."

I've already seen some of it, and I'm here to say - don't freak out. Ninja Tabis are objectively not OP, despite the fact that ever ADCs are building them these days. One issue is the prevalence of strong AD characters everywhere. The other and more pressing problem is that other boot options are too weak at the moment.

crit builds are not the most popular at the moment, with builds consisting of BortK and BC permeating ADC builds everywhere. Attack Speed doesn't synergize as well with these caster builds, so they pick up Tabi's because they synergize with BC's health and BortK's Life Steal really well. These either need a buff, or will become popular again when AS based crit builds do. I'd suggest giving it 5 more movement speed to help it's builders kite.

most of the CC nowadays takes place in the form of knock-ups, which Merc Treads don't protect against. The prevalence of Malzahar Support doesn't help either, because they don't reduce the duration of suppresses, either. It needs a bit more MR, or for Tenacity to reduce the duration of knock-ups, or a little more Tenacity to become a preferred option again.

already a niche boot, the nerfs to it a while ago hit them hard. While it's slow resistance is in a good place, maybe 5 more flat movement speed wouldn't hurt it. It helps that it's one of the cheapest boots to upgrade to, though.

one of the boots that could still manage to get built, there's a lot of CDR everywhere nowadays so these boots fall by the wayside often. I don't think they need changes, though.

still sees use within it's niche.

perfectly fine where they are.

One thing I do notice is the lack of a clear boot option for Slayers. While Lucidity boots seem like they would be the clear option, the CDR offered by BC and Youmuu's remains all that an Assassin really needs. Most Assassins build Tabis because of it, or Mobis if they're feeling lucky. Maybe a new pair of Lethality boots could help them out (With a reduced number of Lethality for ranged, of course), and help those melee assassins find their place again.

Just a few thoughts on boots.