Mine is an indoor cat. He has been on Royal Canin SO since 2007 or so, with no blockages. Before that, he blocked twice, once as a 2 year old and once at age 3. He’s 12 now. No surgery required.
He also gets Friskies canned foods in the pate’ variety only (won’t eat gooey gravies or things with cheese, egg, etc.) as well as fish and chicken and turkey meats from the humans’ table. He loves ice cold fresh water, so I permit him and actively encourage him to drink from the sink. I also bought a PetMate (I think that’s the brand) water fountain. I change the water daily, and I don’t use those carbon filters because I just think they harbor bacteria and biofilms. I think getting them to drink adequate water is a large part of winning the battle.
On a humorous note, I tried a Drinkwell Original fountain first, but it didn’t hold enough water for 4 housecats, and I had to buy the optional water reservoir. It’s just a big clear bottle that clips on loosely. Mr. urinary tract cat who loves to drink from the sink would ALWAYS remove the water reservoir from the Drinkwell and roll it around. I’d come home to a flooded room. So, the Drinkwell got packed away for future kittehs, and I bought the PetMate instead. lol