The John dies at the end series might interest you.

Well… yes and no.

I’ve never read anything else that combines humor, wit, philosophy and phrase-turning in quite the same way.

Some that are at least similar in one or another way:

Lots of Terry Pratchett’s stuff - I’d especially recommend Guards! Guards! or Monstrous Regiment.

Tom Robbins, and especially Jitterbug Perfume

A Confederacy of Dunces by John Kennedy Toole

Kurt Vonnegut, and especially Cat’s Cradle or Sirens of Titan.

Most anything by Carl Hiaasen. He writes in a completely different genre, but with a very similar sense of the absurd.

Will Save the Galaxy for Food by Yahtzee Croshaw.

Rivers of London by Ben Aaronovitch

If you want the same type of humor, Douglas Adams also had the Dirk Gently books.

Terry Pratchett had a similar humor overall, particularly in his discworld series and the book Good Omens that he co-wrote with Neil Gaiman.

But sci-fi wise, I can’t think of any.

If you go back to fantasy, you might be okay with Robert Aspirin’s myth series. The humor there isn’t as close, but it isn’t totally different either.

John DeChancie did the Castle Perilous series that, like the Myth series, has a similar enough vibe to the humor that it might work for you

Sometimes the Phase series from Piers Anthony clicks in a similar enough way, but it’s a stretch to recommend for this tbh. But Piers Anthony is sometimes a hard read in any of his series, no matter how good they are

But Adams is the only one I know of that did that absurdist, dry British humor in that exact style. People have tried, but failed, because they set out to imitate it, which is a fail from the beginning. And I haven’t run across anyone doing it in a sci-fi style that’s scratched the same itch at all