Why is there no mechanical lock on the iPhone?

I recall from older phones (maybe a 3 or 5?) where you had a hard lock toggle on the phone. When you locked it you really locked it.

I have a V14 phone that I use as a phone and a V7Plus phone that I use as an ipod. The V7Plus is in airplane mode with Wi-fi and Bluetooth turned off as they are not needed and just conserves battery. I use passcodes on both devices.

When skating or cycling it is not unusual for a phone to get unlocked through normal movement and start shuffling songs or changing artists, etc.

Why did Apple discontinue the hard locking of a phone?