I have written up a lot of
stuff online too, and a long time ago various people suggested I send it to the UK mags, but they all turned it down, with Flyer saying they have far too much material already and can afford to be picky
I suspect they want nice simple straight stories without the detail which is typical of web reports (one that are worth reading for learning something from). This is obvious - the print format is very different from the web format. One simply cannot capture any real detail in a printed magazine.
One Polish mag (Pilot Club) has run most of my stuff however, slightly edited, so it can be done if you apparently need something for page stuffing. I let them have it for nothing.
There is however a dislike among some printed media people of people who write stuff up for free. I was once castigated by the editor of a certain well known (non UK) pilot magazine for producing free content and doing "creative people" like him out of work
In general, the people I see doing regular print media contribution are people who do not run websites with competing material.