Just as a quick look to see details as to what would be required. Quinoa is hardly the only source of non-meat protein.
Now, yes that does include a lot of protein shake stuff, that's not that unusual for most weightlifting diets. That's also a vegan diet, so you might be able to add eggs, cheese and milk to that diet and cut back on the powder in the meals if you just wanted to be vegetarian.
The powder is of course to solve the issue you pointed out already.
The biggest problem I see with that meal plan is that it is planned for someone with a ridiculous activity level - it reaches "only" 207g protein for 3387kcal.
For comparison, I'm a powerlifter. I'm 238lbs currently. My maintenance calorie intake is roughly 2450kcal on average. I aim for about 2800kcal on training days, and equivalently lower on rest days to roughly meet that average. Fitting 220g or so of protein in that is not that hard: I can eat 400g lean chicken and get 100g protein for <900kcal. I can tack on 100g beef jerky and get another 50g protein for less than <300kcal; which leaves it almost hard not to meet the protein target within my calorie goals.
If I were to eat 3387kcal to meet 207g protein, I'd be adding 1-2kg a week.
That's well in excess of the protein synthesis a typical human male body is capable of. In other words: A substantial percentage would be fat. Quite possibly I might end up adding 1.5kg of fat a week on a diet like that, which would get me quite a lot less protein than what I do on my current diet.
For a body builder exercising heavily 2-3 hours a day, on steroids (otherwise lifting heavily for that long every day would just be a total waste of time), that calorie intake might be reasonable. Or for someone who combines the exercise with a highly active job, like say, construction.
It'd be interesting to see that diet brought down to 2400kcal or below with the same protein levels. I suspect it would look a whole lot less pleasant (and that diet looks awful to me in the first place, but I love my meat).
(Now, protein amounts this high are in the "might as well, just in case" level - the possible incremental benefits hinted at in the literature are as far as I know quite marginal - so a lower protein intake would not necessarily be bad, and then it'd quickly become a lot easier to meet it with a reasonable calorie intake)
Most of the protein shake stuff would not solve the issue for a vegan diet. Most of the protein shake stuff is made from Whey or Casein or egg whites which IIRC are not vegan. There is pea protein or hemp protein but my quick googling tells me is high carb and low protein and can easily throw you off your calorie limits.
Both pea protein and soy protein products with comparable protein to kcal ratios are available from the company I buy my protein from.
I'm not vegan, so I've never bothered trying them, but it doesn't seem like it'd be a big problem.
My concern (see my other comment) would be that the diet shown certainly is extremely high calorie, and it looks like it'd be pretty much all nasty shakes to get it down to a more normal level with the same amount of protein.
(EDIT: Note, this would only really be an issue if you do heavy resistance training, as the protein level in that diet is very high for someone who isn't doing weight lifting)
Just as a quick look to see details as to what would be required. Quinoa is hardly the only source of non-meat protein.
Now, yes that does include a lot of protein shake stuff, that's not that unusual for most weightlifting diets. That's also a vegan diet, so you might be able to add eggs, cheese and milk to that diet and cut back on the powder in the meals if you just wanted to be vegetarian.
The powder is of course to solve the issue you pointed out already.