Has anybody opened an account with Zerodha recently, if yes, what is this power of attorney form which they are asking you to sign, is this the standard procedure?

Yes, its a standard procedure.
In easy example, think of banking terms. suppose you deposited Rs. 1000 in bank account. you have your agent who deals on your behalf and he deposits and withdraws everyday. now bank cannot give access to your agent unless he has an authority letter from you. Then bank registers your agent as authorized person who can transact on your behalf.

Similarly in share trading, Bank is CDSL/NSDL , agent is Zerodha and you are you.

Zerodha needs authorization from you to withdraw shares on your behalf from CDSL. CDSL will approve zerodha as authorized person and allow them to withdraw and deposit shares on your behalf.
That’s why its mandatory to provide POA.
Happy trading.