No, in fact it's pretty much the opposite - while the FA told AR's not to use the flag across the chest signal, this is based on official guidance and a joint recommendation from several football authorities to do precisely that.
Highly appropriate in my opinion because when this was first brought in, virtually nobody except match officials would have been aware of the change and this was an easily understood gesture to explain what was going on.
Here is the relevant wording from the memo issued jointly by the FA, EFL, Premier League and PGMOL.
The full document is available in the "Resources" section of this site.
https://www.refchat.co.uk/threads/a...ffside-offence-in-the-players-own-half.14653/