Yes if its on Software Engineering Exchange, it has to be an opinion-based question, no harm in discussing the opinions in a Software Engineering exchange.

Whole Subject "Software Engineering" is purely based on an opinion-based recommendations related to a given time,

I can understand if its only Stackoverflow exchange, it needs a definitive answer, Coding questions, Maths questions has only ONE correct answer, But "Software Engineering" is NOT a definitive answer, we have to weigh pros and cons of the each metrology and to know them we need to have opinion based answers.

Besides if I ask "What is Software Engineering", am sure answer will vague across the community, every single developer has their own view of "What is Software Engineering", Topic itself is a opinion based and its funny to ban it in this exchange,

If you don't agree just browse through the questions and answers in this Exchange, You will realise they don't have any definitive answer at all all opinion based.

Yes if it's on Software Engineering Exchange, it has to be an opinion-based question, no harm in discussing the opinions in a Software Engineering exchange.

The whole Subject "Software Engineering" is purely based on an opinion-based recommendations related to a given time,

I can understand if its only Stackoverflow exchange, it needs a definitive answer, Coding questions, Maths questions has only ONE correct answer, But "Software Engineering" is NOT a definitive answer, we have to weigh the pros and cons of each methodology and to know them we need to have opinion-based answers.

Besides if I ask "What is Software Engineering", am sure the answer will vague across the community, every single developer has their own view of "What is Software Engineering", Topic itself is a opinion based and its funny to ban it in this exchange,

If you don't agree just browse through the questions and answers in this Exchange, You will realize they don't have any definitive answer at all. All ideas questions are somewhat opinion based.