it was removed for good reason and there is absolutely no benefit to adding it back.
Is OP_CAT happening?
The covenants proposal was recently assigned BIP 347, and now it's up to the community to decide. Blockstreamer Kiara Bickers breaks down the pros and cons and attempts to answer the question on most Bitcoiners' minds: Is it safe?
https://blog.blockstream.com/op_cat-the-purr-fect-solution-for-covenants/
Discussion
It was remover for a very specific reason that has been addressed in the proposal. You may still believe it should not be added however the original reason it was removed should not be one of them as it is a trivially addressed vulnerability.