I made a 1d6 table of random rooms for a game I'm working on

That's awesome. How do you handle backtracks that don't line up?

This is awesome and I highly recommend this approach. I've used something very like this in Pathfinder (1e if you're wondering) for a series of natural caverns occupied by Skum and it worked out great. I didn't so much work loot and monsters into the plan. I mostly just used it for the shape/layout of the caverns. But I can definitely see benefits to having more worked into the roll table system.

If you want certain things to happen at intervals through the dungeon or whatever, just skip rolling every 4th time they explore a little further and instead put in in what you want them to run into.

Also, when I did it, I found it worked nicely to consider the results on the roll table "suggestions". Like, if you roll 1 four times in a row, in a TTRPG situation, it could end up being like "ok, there's more hallway." "I scout ahead further." "More hallway." "Ok, further then." Mor-" "Let me guess, more hallway."

Here's the (d20) roll table I used for the aforementioned Skum dungeon if anyone's interested:

1.    --- (straight)
2.    +
3.    U
4.    L
5.    -< (fork)
6.    -w- (water)
7.    -O
8.    -e
9.    stairs
10.    -=== (widen)
11.    converge
12.    -[s]| (secret passage at T)
13.    =-= (narrows for short distance)
14.    T
15.    --
16.    Overpass
17.    -<>-
18.    s (spiral up/down)
19.    -rubble-
20.    ---o (fake dead end)

I want to say I made a slightly improved version later for a different campaign, but I haven't been able to find it. I might search more later if I have a second.