Some modern laptops have completely removed support for S3 sleep, as well as some still include it but clearly never tested it. I have seen multiple OEMs that have S3 sleep “available” but with the Windows installation utilizing S0 by default. If such OEMs are lazy (which a lot of them are), they just won’t bother to properly test the functionality as long as the default OS configuration they ship works. Same kind of deal now with how many OEMs (mostly used to) ship non-standard ACPI implementations that required extra drivers in Windows to function (or would just not work correctly under Linux).
Some modern laptops have completely removed support for S3 sleep, as well as some still include it but clearly never tested it. I have seen multiple OEMs that have S3 sleep “available” but with the Windows installation utilizing S0 by default. If such OEMs are lazy (which a lot of them are), they just won’t bother to properly test the functionality as long as the default OS configuration they ship works. Same kind of deal now with how many OEMs (mostly used to) ship non-standard ACPI implementations that required extra drivers in Windows to function (or would just not work correctly under Linux).