The OP said 'survival situation'; one of the common problems in 'survival situations' is lack of clean water. You can carry all the dehydrated food you like, but if you can't get water, it's pretty much useless.
Baked beans are only low in energy density if you ignore the water content. Water is more important than food for survival, so I reckon you can't really go wrong with baked beans.
There are probably worse options, but in the long run you wouldn't be in a very good state if you couldn't get fresh food.
One major problem is that beans wouldn't supply all the amino acids you need. Cultures that lack abundant sources of meat and must needs fulfil some of their protein needs from plant sources combine different sources. In parts of the Americas they made shift with the "
three sisters"squash, maize, and beans. Baked beans on toast (which is what people often do eat in practice) would be betterbut then you'd need to store (or make) bread, so your storage needs go up.
Canned beans are also very low in fat. They'd work out to about 3% fat, 20% protein, 76% carbs. Humans can probably tolerate a fair range of variation in macronutrients, but this is very low in fat. Ancestral diets in the Stone Age (i.e., almost all of our biological past) were probably around 65% fat, 15% protein, 20% carbs; we're a long way from that on beans. On around 3% fat you wouldn't be getting what you need for biological processes and would probably start having seizures after awhile.
Here's what the nutrient profile of 8 oz. of canned beans looks like:
It's not too bad in some ways, but you have to take into account that not every nutrient that's present there is necessarily in a bio-available form. Worse, notice that the vitamin C content is so low as not even to register. There's also no vitamin D and the vitamin A content is negligible: those two are very important nutrients, and you really don't want to go short of those. Vitamin D is unusual in that you can synthesize it in your skin from sunlight. (A form of cholesterol contained in skin (7-dehydrocholesterol) is converted into the precursor of Vitamin D, called cholecalciferol.) But, well, it had better be the right time of year and the ability to do that drops off with age. Of course, you'd get some A, D (and K as well) from good quality butter from grass-fed animals, so if you put that on the toast ... but now you have to store butter as well as the bread and the beans.
I'll also note in passing that the beans are not supplying you with vitamin B12. That's a highly important nutrient:
Vitamin B12 deficiency can potentially cause severe and irreversible damage, especially to the brain and nervous system. These symptoms of neuronal damage may not reverse after correction of hematological abnormalities, and the chance of complete reversal decreases with the length of time the neurological symptoms have been present.
Link
The beans would probably be filling in an emergency, but if they were all you had you'd better be setting some snares or something before very long.