Max-Age / Expires on Cookiebis

[Jxck]

NOTE: Some existing user agents do not support the Max-Age attribute. User agents that do not support the Max-Age attribute ignore the attribute.

https://www.ietf.org/archive/id/draft-ietf-httpbis-rfc6265bis-11.html#section-4.1.2.2-3

Is there any known client which doesn't support Max-Age attributes ? or is this Note still really necessary for current world ?

removing this Note could urge using Expire to Max-Age (it's precedents) and will solve some problems around parsing DateTime format. and IIUC it's the motivation for adding Max-Age onto Expires
Same things happened on Cache-Control: max-age and Expires: and RFC9111 doesn't has note like this.

But if this Note still valid, developer still required to use Expires (and from point of avoid duplication, no Max-Age maybe).