At the moment the trend seems to be to sing in the same pitch that we speak which will make many songs seem 'too high'. The fact is the voice is a muscle and if you don't use it you lose it (so to speak). Singers, like athletes, must practice to keep their ability. I am not saying that everyone needs to do scales and such, but using your singing voice more often will increase its flexibility.
Of course in times past people had sing-a-longs, more people were members of musical societies, sang in church or were members of church choirs which gave them more opportunity to use their singing voices. And it started from an early age, there was more focus on singing at school - assembly required a hymn and music lessons included singing. Nowadays children are lucky if there is any music programme at school at all. Though I know there has been a rise recently and I do hope this continues.
music also has a lot of effect on this perception, as many pop singers release songs that are rather low, not because singing voices have dropped; more because of the use of close microphones. If you have a mic only 1 inch from your mouth, you need virtually no projection and so you can sing much lower notes than those you can achieve when trying to sing without a mic. People try to imitate this 'pop' sound and technique, so when they try singing hymns in the same way it all seems 'too high'.
At the moment most hymns rarely go above the stave and therefore do not require any true height in the voice. So suggesting that we should look at lowering them seems ridiculous to me. My main complaint about hymn singing at present are two:
- they are too low!
- they are too slow!
Don't go with the cop out of 'it's too high!', have the commitment to continue singing and with more practice/experience at it, you will be amazed how high you can sing. Voices really haven't changed when speaking in terms of hymn keys, so, say no to low!