What is the scope of doing an MBA after 2020?

Depends on the company. Statistics and finance is very important to analyse business. If one looks at the fact, small scale, large scale does management based on objectives and it is profit maximisation. That means management is revenue based and not management principle based. So, management principles can be used as good etiquette and sound organisational behaviour, but, revenue based management uses waste elimination and other scientific techniques to reduce costs. So join ACCA which is actually 2 years. MBA discipline is good as well and nothing wrong about it as it introduces one to economic analysis. 

Supposing if here are sound foundations of a management, then

• Division of Work- ... demands drives business expansion, human capital,revenues and expenses, job needs to be done and labor laws restricts one person doing multiple chores, hence division of labor.
• Authority and Responsibility- ... to control and monitor that resources are not overexhausted in a manufacturing unit. At office, get the job right to earn profit or sustain in the market.
• Discipline- ... Task achievement, 100 targets per day achieved will earn 1000₹ revenues. This is an employee psychology if he is disciplined or retarded.
• Unity of Command- ... performance management define hierarchy as tactical, strategic and operational. 
• Unity of Direction- ... all workers work for their a common goal, employment, and company earns money under above stewardship. This is economics. 
• Subordination of Individual Interest- ... this is the reason why managers exist. 
• Remuneration- ... motivating factor for employees. Employees are consumers again. Company earns profits again. 
• Centralization - to earn profits through cost reduction. This is cost management. 

Like this there are other principles which aid in business administration to reduce chaos at work place.

This can be achieved through Law of courts as well. Example, law can be created to be polite, work only without wasting time, do the job as directed etc. while profit maximisation can be achieved through other professionals. What part an MBA plays, core part - Consumer behaviour and marketing strategy sometimes using statistical means by understanding economics. The future of mba in 2021 is something personal to everyone and what they perceive about it. 

Strategic, tactical and operations was there even before an mba discipline. Now a days it looks like nothin is important.