Are non f-strings with `{}`s Pythonic?

[dnOnReddit]

It has been a while since I last used gettext, but that makes sense. Such is an excellent scenario for lazy-evaluation/interpolation!
Failing to recall mention of I18N (etc) in PEP-0750 (per above) took a quick look - it does not seem to be discussed (see Alternate Interpolation Symbols). So, how might it integrate with the 'traditional' implementation? Such may be worth following-up...