I figure that if Triumph decided that the filter could be so hard to change therefore it doesn't need to be changed that often.
My car is the same, remove the wheel, mudguard etc 1 1/2 hour job for a stupid gas filter. I first changed it after 7 years 130000km 80,000mi. Looked allright and no sediment came out of it. It had surface rust
It's not like the old carb filters that would clog up so easy, they were so tiny.... these are big filters and IMO can last a really long time.