yes the vents need to be cleaned a few times a year depending on use, volume & what's being dried. Flannel sheets cause lots more fluff in the catch screen. The catch screen needs to be cleaned every use. I was a VFF for 20yrs & responded to a few dryer fires. Even had 1 in a house I moved into a month earlier, years back. I was on the Vff in this small town & had been 1 for many years, so when I smelled smoke & saw what it was, I knew what to do & how to put it out, as it was not not that far gone yet. Dryer was screwed from it, plus some minor damage in the exhaust venting area. I called my insurance about a claim for a new dryer & it was denied as the FD was not called. Shock my head, said I'm on that FD, so I put it out without the need to call. If a called it in & went to the fire hall to respond, that time would have caused more damage. Hung up the phone frustrated, called the Fire Chief to get an incident # & called back to Insurance. Got someone else & the claim went through. I used to have my heating ducts cleaned every 3-4 years & the dryer vent done then too.
I never dry clothes now when not at home & clean out the vent regularly with a vacuum & compressed air My current house is slab on grade with in floor heat, so all I need to clean is the dryer vent. Dont forget to clean your bathroom exhaust vents too if you have one. My bathroom exhaust fans are all on timers, so they cannot run more than 1hr. I responded to a few of those too. too may people leave the bathroom exhaust fan on way too long & they can over heat with a build up on dust & dirt.