Why would we? It "just works". We've only changed how we write the letter "ż" some 30-20 years ago. It was previously "ƶ". Also, "ż" and "ź" are not accents but separate alphabet letters.
There was no typeface change for “ż” - the other typeface is sometimes used now as it was 30 years ago. See the foto at Wikipedia: https://en.m.wikipedia.org/wiki/%C5%BB
And yet, you can see the "Straƶ Miejska" logotype linked in my comment above, with a crown on the eagle, so post-December 31, 1989[0].
It may depend on the region (I was raised in the eastern Poland) but I also remember that in the primary school we used a different symbol for the letter "s". But only in hand-writing while any printed "s" looked like it does currently. I'm unable to find the UTF-8 character resembling the hand-written version.