As a plumber I’ve had more problems with low flow toilets and long runs of 4” drain lines. There is simply not enough water per flush to clear out the main line of solids. The blockage then builds with every subsequent flush.
I’ve reconfigured many drain lines to prevent blockages. I simply tell the homeowner to thank the government for the added expense.
Now to add insult to injury, the newer toilets use even less water than the “older” low flows. (1.28 GPF)
The toilets also do not have enough water surface area in the bowl to begin with. This results in increased cleaning. I won’t get any more graphic than that.
I have a newer toilet that flushes a maximum of 1.6 gal. but, given its druthers, will go with a lot less and a miniscule water spot. Unfortunately, if I use it in the low flow configuration and do not hold the handle down to allow the water spot to fill, it rapidly ends stinking of stale urine. Its other “charming” feature in the small spot configuration is there’s a gyeser every time I flush it, really intersting if I’ve passed a musher or am flushing a dog accident down.
What does that require? How do you know when to reconfigure, and when to just get a better toilet?