At least a couple of things at play here.
The first is even with low-and-slow, you normally get to above ~130F within a couple of hours. Then it spends many hours in the 150-190 range (the famous brisket stall). That is the area where tenderization happens anyway so there isn’t much point to spending lots of hours at 90F. When the meat surface temperature is colder is when you get the most smoke adsorption, but that only takes a couple of hours, no need to spend 6 or 8 hours at low temperature.
On the way up, even if there is bacterial growth, it will get killed once the higher temperatures are reached. Higher temperatures also denature many of the more serious chemical toxins produced by bacteria. So it is generally a much bigger problem to spend too much time in the danger zone after cooking.
Lastly, the biggest risk is surface contamination, the interior is not generally contaminated. Even if it takes hours for the interior of the meat to reach above 130 F, the outer surfaces reach that temperature quickly and prevent bacteria growth and kill it at higher temperatures. A notable caveat to this is that a lot of the cuts that are frequently cooked low-and-slow are also tenderized with a jaccard tenderizer which can push surface contamination deep into the meat. If you do this, you should be careful about it. This is especially an issue for more naturally tender meats that don’t have enough fat to withstand cooking to 195F. Meat that you are going to cook medium rare should not be jaccard tenderized – and also shouldn’t need it.
I wouldn’t let a piece of raw meat sit out on the counter for 24 hours and then cook it, but I wouldn’t worry about the 4 hour rule while it is actually in the smoker.