I have always been fond of defensive setups where you can switch 1-4 if you have a big PG and a quick footed PF but to stay home at the 5 spot. Keep your center on the opposing big so that your main shot-blocker is at the rim to contest shots and to grab rebounds.
It was one of the things I liked so much about the second three-beat Chicago Bulls with Ron Harper at PG and Dennis Rodman at PF next to Pippen and Jordan. Four guys all around the same size who could switch seamlessly when required. Then Longley who couldn't switch onto anybody.
The 80s Lakers were another example with Magic and Cooper in the backcourt, Worthy and AC Green in the frontcourt. AC Green was so versatile defensively with that speed. Kareem, again the center, could not switch onto anybody. Old man Kareem at this stage. So he always stayed home.
Difference is, Longley and Kareem didn't have to guard stretch bigs on the perimeter. This ain't the case in today's NBA. The game has come a long way since the 80's and the 90's.
Yet at most a third of all centers are actually capable 3-point-shooters. Look at the playoffs this year.
Here are all the starting centers for the 16 playoff-teams (with the exception that the Clippers have generally started without a 'real' center, so that's Batum for completeness) and I grouped them as "good" shooter (>33%), "bad" shooter (<33%) and "non"-shooter (0%).
Good shooters: Jokic (38%), Embiid (39%), Brook Lopez (34%), Griffin (39%), Batum (39%)
Bad shooters: Valanciunas (25%), Nurkic (20%)
Non-shooters (0%): Gobert, Adebayo, Capela, Ayton, Drummond, Marjanovic, Thompson, Gafford, Gibson
So in most cases the opposing center isn't going to be a big thread on the perimeter. And I actually disagree on Timelord not being able to guard stretch bigs. And yes I acknowledge guarding Jokic or Embiid is a problem, but they are a handful for anyone.
All teams have
at least one stretch big. The Jazz are the only team that practically never used a stretch big, probably because they are built around an elite rim protector in Gobert. Here's your list regarding teams with non-shooters:
(these are regular season numbers, cannot find the playoff numbers)
Jazz: Ilyasova (played 43% of his minutes at Center, but he hardly ever played)
Hawks: Collins (played 36% of his minutes at Center)
Heat: Bjelica (played 43% of his minutes at Center)
Suns: Saric (played 78% of his minutes at Center)
Lakers: Marc Gasol (played 100% of his minutes at Center, was a starter prior to the Drummond acquisition)
Mavs: Porzingis (played 82% of his minutes at Center)
Celtics: Kornet (played 100% of his minutes at Center)
Wizards: Thomas Bryant (played 100% of his minutes at Center. Unfortunately for the Wiz, he was injured.)
Knicks: Randle (played 24% of his minutes at Center)
Playoff basketball is mostly about exposing your opponents weaknesses. Teams got plenty of time to prepare for the games, hence they focus on exploiting mismatches. If one team has a Center who cannot defend on the perimeter, chances are that the opposing coach will single him out. It happens all the time, even with Gobert who's an elite rim protector. The Clips were shooting 43.3% from 3 vs the Jazz, exactly because Gobert cannot play D on the perimeter.
Regarding Timelord:
Just check it out yourself. Here's a short video of Timelord trying to switch the Ibaka-Lowry PnR. Lowry blows by him as if he weren't even there. Can't find a long video with multiple plays like this, cause he pretty much always drops back and protects the rim. I mean, this is nothing new. Feel free to focus on his PnR defense when watching the games.
https://www.youtube.com/watch?v=JtIt8QoNyqI