How to convert a bytea column to text?
How can I get rid of this encoded, so that I only see the original
value of the column, in the text format

Bytes have 256 possible values, when there are only about 95 visualizable ASCII characters, (the range [32:126]), so the mapping between ASCII text and binary representation cannot be one-to-one.
The format produced by encode(metadata::bytea, 'escape') is just one possible representation, where some bytes are represented by sequences of characters. Others common representations are hexadecimal (outputs each byte as 2 characters) and base64 (outputs each 3 bytes as 4 characters).
If you don't want these and have a specific idea on how your metadata column should be output as text, then you can always provide a user function instead of  encode. Right now your question does not specify what output you want to see, only that it's not the escape format.