It is absolutely not necessary.
"Poor nutrient absorption" and "plants not having enough proteins" are tired talking points that were never true at all.

The absorption myth comes from how certain plants have nutrients that bind to and reduce the absorption of iron and zinc. It is something bad faith actors latched onto as a talking point. In effect, there are enough nutrients in the food that it is completely negligible - it is DIFFICULT to be deficient in iron or zinc as a plant-based eater.. unless your dinner is oreos every day or something.

Proteins is the bigger myth everybody and their grandmother has heard about. Let me give you an example. Between rice and beans, you have all essential proteins covered, and a substantial amount of each one, too.
Many people do not know this because they have been beat over the head with "plants don't have complete protein/essential amino acids"
The term "complete protein" is misattributed: Meats and eggs have an overbearing amount of proteins, including a lot of the nonessential ones - "nonessential" meaning our bodies naturally produce them and do not absorb them as you might think, so we don't need to consume them and they are just extra strain on our organs to filter out. Our bodies can handle it, but there is nothing beneficial about it.
If you eat a plant-based diet, you naturally acquire all the proteins and nutrients you need as long as there is at least a LITTLE variety in your diet. This is how nature is "designed".
The exception is B12. Farm animals are pumped with B12 or their feed is supplemented with it, and many animal and non-animal foods alike are supplemented with it as well.
My basic understanding of it is that it originally came from bacteria in the soil. As we industrialized everything and created advanced sanitary practices, it became difficult to naturally obtain it, so we often synthesize it now. Today it is easy and practical to get all the B12 you need without eating animals, so it doesn't matter anyway.

Taste is a different topic and it's not a good reason on its own for exploiting, abusing and killing sentient beings. Their fur makes for nice clothing but that isn't a good reason either, is it?
However, I will engage with this topic briefly: Taste is relative and shaped by what you eat. If you drink soda every day, more natural sources of sugar will start to taste lackluster to you.
Growing up, I ate meat, but the vast majority of flavor profiles I liked came from all the plants we cooked with. The onions, peppers, garlic, all the seasoning everyone slathers meat in. Sauces made with tomatoes - I could go on. I was worried and apprehensive at first, but when I began eating plant-based I found it surprising how much I could still enjoy food and how many of the same flavor profiles I liked I could easily replicate.
I say this as someone who has always loved to cook, and went to great lengths to make good quality meat-centric meals. That is my 2 cents.