The “Snow Leopard effect” is more about the transition to Intel from PowerPC than the OS itself.
And maybe I’m a minority but the latest macOS is not worse than previous editions, for instance I use Sequoia on a M1 Mac but also 10.4 Tiger and OS 9.2.2 on a PowerMac G4 (MDD, 2x 1.2Ghz with 2Go of RAM) and the stability is not worse on Sequoia than Tiger or 9.2.2, in fact I have encountered more crashes in 9.2.2 and Tiger than Sequoia and all macOS 11+ (except Big Sur who has rough edge on beginning on M1 device)
And maybe I’m a minority but the latest macOS is not worse than previous editions, for instance I use Sequoia on a M1 Mac but also 10.4 Tiger and OS 9.2.2 on a PowerMac G4 (MDD, 2x 1.2Ghz with 2Go of RAM) and the stability is not worse on Sequoia than Tiger or 9.2.2, in fact I have encountered more crashes in 9.2.2 and Tiger than Sequoia and all macOS 11+ (except Big Sur who has rough edge on beginning on M1 device)