I tend to see recommendations of 5-10 times turnover of the tank's volume per hour, and many do more or less with fine results, including 0 turnover even for some filterless low tech planted tanks. With quite a wide range of recommended flow clearly flow isn't necessarily that critical a factor.
There are however many different factor to consider here, every tank will have different things affecting flow patterns, different fauna bioloads, different flora amounts which also can help maintain water quality, different light levels affecting the effectiveness of plant metabolism, etc.
The actual effectiveness of different filters mechanical filtration, and how long that will last before becoming ineffective and requiring cleaning is a different matter as well.
And perhaps filter media volume is more important than flow, if a given tank requires bio-filtration and if the plants aren't doing the entire job.
So how is that for a completely indeterminate answer to your query?