Why do girls like soft toys particularly teddy bear?

They are very big and very soft. That size will give a feeling that there is a human companion with them. That softness gives a feeling to them that the companion is a very kind-hearted person.
It is a human tendency for all to tell their problems. wishes and other requirements to their parents when they are young. Sometimes they may have a fear to tell directly to their parents. So before going to the mother they will practice by keeping the soft toy in the front and do the rehearsals thinking as if they are speaking to their mother. This will make them fearless.
Many girls keep that toy by their side even when they are on their bed and thus they feel that there is a companion with them 24 X 7/

I do not feel this could obviously be the case however this would depend on the observations from person to person. Usually, the parents or the adults would want their children or the kids to behave or act in a certain way. Their toys would be chosen accordingly since the time they are still very young and not experienced enough to think of good or bad including with respect to the choice of activity that one should get involved with.

The existing times is required to be practical and rational to the things taking place around us and the children are grown considering this and quite obviously the choice for girls would be different. We would have witnessed a girl child playing with a baby doll but this even for a period of time.

I am not agreeing with the author's viewpoint for one another reason how many houses would be witnessing these huge soft toys?

The girls are very shy and sometimes introvert and they find sometimes difficult to express their feelings honestly before the parents. They are constantly looking for some means which could provide them relief with some light entertainment. At least the the toys seem to their best platforms for their outlets of emotions- both joys and sorrows whenever they are in dire need of a true companionship.
As we see that the present trend of the parents is to ignore their kids due to work pressure or the constraints of timings. They don't have enough time to interact with their loved ones. Hence the girls like soft toys to vent their emotions before such soft toys. Their one way of communication also provides them psychological relief which is essential for their better mental growth.

Like many stereotypes created in society about young girls and boys liking certain colours, toys, sports and subjects. This is one from the very beginning of childhood children are conditioned in certain ways and this conditioning further decides their likings and disliking. Girls particularly are made to feel that they have to show certain behaviours even if they do not match their personality among such traits is the expectation of girls liking soft toys.
And it has now become a norm that we gift such toys to small kids and young girls as well. Sometimes even under peer pressure, people show such liking. I am not saying that girls do not like soft toys they actually do in many cases but this is not always true and hence can not be generalised as the preference of girls, but one of such stereotypes. Often in many households, a girl's desire for having toys like video games, football, cricket and crackers is discouraged and they are taunted as well and such things stay with them. On the other hand, the culture of giving teddy bears as a gift during valentines day, birthdays and some other occasions by peers and friends as well have enforced this stereotype in a stronger manner so just assuming that most girls like soft toys will not be the correct thing to say.

It is also one of the stereotypes like another stereotype. In early times many people used to say that a boy child likes to play with guns whereas a girl child likes to play with a doll. But in reality, It does not apply to all children. Generally, girls are more emotional by nature than boys. They always like soft items because of their emotional nature. They dislike hard items. Some girl child wants to sleep with soft toys so that they feel anybody are present beside them. Some girl children are habituated to this extent that they can't take sound sleep without it. In soft toys, a Teddy bear is very soft. So, most people like it and keep it in their house. Soft toys like Teddy bear always make us feel that someone is present near us and we are not alone. It is a good Item to rehearse any speech and music program. Keeping in front of participants any rehearsal can be done.