Airlines' flying stock is aging...as we all do.
Maintenance, as with all expenses, becomes a 'commercial consideration' so aircraft are neither maintained, nor replaced as frequently as 'should' occur.
In Oz we had 'Ansett airlines'....went bust...a lot of people lost work, etc...but it was actually a GOOD THING. Ansett was one of the 'oldest commercial carriers'...in that their 'fleet' was past its use-by date, and, strapped for cash, corners were being cut.
Now that they are folded many of their aircraft are 'rusting' in the Mojave desert...and rightly so.
If you compare notes....Qantas has the world's best safety record of all the carriers.....turns a profit, but the FAA is having to stamp its feet to get them to not 'slacken' their maintenance regimen.
My father worked 30 years in Flight Service [like ATC] and has some 'fun' tales to tell.....like the QF Jumbo that landed in Sydney with tree branches in its undercarriage......
He personally prevented a 'mid-air' through noticing a radar error....usually a near-miss is measured in miles...this was a case of the 2 pilots being able to wave to each other.
Over the past decades flying has become more affordable but the aircraft costlier to replace. Those two factors make 'incidents' more common, not less.
As to comparative 'safety' of travel modes....that's usually calculated as 'passenger miles', not 'trips', so, like any statistic it can be redefined to suit whatever you wish.
I haven't seen a stat that counts the number of plane flights in a year multiplied by passenger count divided by fatality compared to vehicle trips ditto. The comparison then may be less favourable towards flight.
It's a bit like the claim that cycling is healthier...even though you are breathing in car fumes....the car driver actually gets more as he cannot escape the vehicle....sounds good until you factor in crash 'survivability'...example...I've had 2 cars written-off from under me and managed one stiff-neck....bicycles have hospitalized me 3 times....