Nah man its not bad, not as tasty as fresh veggies or a just baked chicken but I eat canned tuna and canned chicken breast all the time, but i mix in some mustard, relish, paprika, etc. to spiff it up for flavor.
Canned beans are high in sodium but frozen has much less, although neither is as tasty as fresh. Canned tuna and chicken breast are good I eat those on the regular, they're a great source of protein. Overall fresh is better but on a budget frozen is better if you can make it taste good, which is doable.