Unless I'm missing something, we've lost 11 clubs (in one form or another) since the end of 2019 according to the annual reports.
UOW were involved in Subbies but, as soon as COVID hit, have had no presence since then.
Engadine, Dee Why/Terrey Hills haven't played since 2020 (although Terrey Hills ran a Halligans in 2023).
Menai missed 2020, came back in 2021 and 2022 but haven't been seen since.
Combined Forces joined in 2020 but haven't been seen since 2021.
HAC left in 2023, Camden played Halligans that year but didn't in 2024, Rockdale came and went in 2023 too.
If both Harbour and Dukes are gone, that's nearly 2 Divisions of clubs lost.
Then you look at teams like Wakehurst/Brothers and LCOI who essentially take 4 clubs down to 2, only gaining (on a permanent or hopefully-permanent basis) Georges River and Penrith, it's not a good sign.
tl;dr - 56 clubs have played in Subbies in one form or another since 2019, 11 no longer do.