That tartare looks great.
Things I buy in cans instead of going fresh:
Tomatoes (crushed, diced, pureed, whatever). I've gone fresh and with cans and I just prefer cans. I feel the taste is indistinguishable and it's much easier. Exception might be Indian food where I can simply throw ginger, garlic, onions, and tomatoes into a food processor and liquefy them.
Beans. Fuck soaking beans from scratch. I've heard an instant pot makes it easy but I still haven't bothered. They're just fucking beans - how much better can they get fresh?
Chickpeas. Similar reasoning to above except chickpeas are even more of a pain in the ass.
Some veggies. Like corn. Fresh corn is tough to find in CA anyway.