DS9 did great for 7 years. It needed to end because it had run through the premise sufficiently, but getting tangled up in canon was never a problem for them.
What they needed was a fresh premise. I was rooting for the Dominion to win the war in the series finale, half the DS9 cast to get killed, and for a new series to start called Star Trek: Resistance
, with the surviving DS9 characters, plus some new ones and I wouldn't have objected to some VOY characters joining the show (Tuvok, B'elanna and EMH would have been good choices) when that series ended.
Canon has never been Star Trek
's problem on TV. The problem has been writers and producers afraid to take a risk (which is why VOY and ENT were creative failures) and underlying changes in the TV biz (which is why DS9, VOY and ENT's ratings kept sinking and why it would be hard for even a great Star Trek
series to survive now.)