Hi Ankur,
You will be aware that AEM is WCM tools and React is front end dev JS
I have seen a lot of people asking the similar question. If react is new, it doesn't mean it has to be used. As long as you don't have strong reason to use it, no point of putting it into a project for the sake of AEM + React Integration.
Your questions are too generic and most of them depend on what requirements you have ... there are many other JS frameworks available. From those you need to pick which serves your need best and saves time.
Like
- What we can't achieve if we don't use react?- I would simply say, you will miss the features and benefits of react
Every JS frameworks come with pros and cons, you need to pick based on your needs.
I would recommend you to go through react documentation, understand it well. I am sure, you will get better clarity.
I am sure you may not like this answer
but at the end, it all goes down to what purpose you want serves with JS in site, is there specific requirements that cannot be achieved by jQuery and you really need react to achieve this.
Thanks