A couple of things stand out to me:
First, you define religion as "the adult systematic study of how best to live our lives" - but there is already a word for that - ethics (which word you also use frequently when discussing religion as far as I can see so maybe you are conflating the two).
YES!! Not
conflating the two, but saying that Religion is a
cultural activity the
purpose of which is to optimize our
ethical beliefs. Absolutely! That's what sermons and other such presentations are. That is why people study religious literature. For
self-improvement. Did you check out the notes regarding ethical beliefs and existential beliefs?
Second, you make the point that the tendency to assume that "religion" implies beliefs about the existence of supernatural entities (deities) is erroneous on the grounds that some religions don't have such beliefs - i.e. are "non-theistic". I agree to a point, but would also note that there is also a tendency for "non-theistic believers" to avoid calling their beliefs "religion". E.g. - you will often hear Buddhists (not all of them of course) say that Buddhism is not a religion.
Is not Buddhism widely considered one of the world's major religions? So we should change the definition of Buddhism from what most people consider it to be?? Just to be able to look down upon Religion? (
Why do people want to make sure that they are not considered to be involved in Religion?) Do we want to continue the tendency to demonize well-meaning people? Can we not improve?
In English usage though - since about the 16th century, the word 'religion' has implied reliance on/obedience to a higher supernatural power(s).
Because
most religion is like that.
But not all. Are you assuming that whatever is done by almost everyone is obviously the right thing to do? I don't make that assumption. If everyone thought Earth was flat, that wouldn't make it so. (I realize that a definition is not the same as a proposition, BTW. But there are consequences of a bad definition, one of which is the promulgation of faulty thinking.)
And then there are the
consequences of continuing with an incorrect definition (incorrect for the reasons given), which can lead to mistakes and perhaps significant PSDED. We have to allow for progress in whatever we are doing, right?
A definition is of the nature "X is all Y of which Z is true."
A definition is not of the nature "X is all Y of which Z is true of some."
Maybe you could coin a new word if you are promoting concerted and inclusive human effort: "rely-gion" (meaning a system of beliefs that promotes mutual reliance for mutual benefit - but maybe that sounds too much a like an insurance sales pitch).
Or, since as I mentioned above, you might be conflating ethics and religion, how about "ethi-gion".
And the consequences of that would be, in my opinion, the destruction of the Humanianity concept, in addition to making it easily laughable by those prone to ridicule.
One of the important aspects of Humanianity, IMO as a Humanian, is our overcoming our tribalism, which has us fighting and killing each other all over this planet. To foster the current tendency to exist in groups that look down upon one another --
rather than to incorporate within our groups the ability to have difference of opinion, with the continuing effort to work together toward agreement to that which is accurate and optimal -- is to continue that tendency. I am for Religion. Much good is done by Religion, right along with the bad. It is not true that religions are just groups of bad people. I find most participants in most of the religions to be highly motivated to do good things for their fellow humans. Of course our human tendencies toward "corruption" get into our religions to some extent, as they get into whatever else we create. The problem is
in us, and from us it gets into whatever we do. But we also do good, a lot of good. We don't stamp out children because they are not mature; we help them to mature. We need to work on ourselves, our species, and we need therefore to work on our religions. Religion can improve. And it is improving. It's just that our species is still just a toddler with significant behavior problems.
IMO (being politically correct)