It is sad that love can be toxic because as you wrote, it shouldn't be but for the gatekeepers. And then there is the issue of where the line is crossed (is there really a line?) between affection and love.
There are "approved" loves; romantic with whomever the gatekeepers approve. Non-romantic love of kin, etc. Then there are the ones with gatekeepers, which sometimes are the ones in our own minds.
I have love for non-kin, not my wife women. Some could be romantic if I allowed it; a toxic thought where my internal gatekeeper shoots guilt darts at me. Would my wife understand? Kept in a dark place.
I have love for male friends. Not romantic and I have no problem giving them a hug without a "no homo" backslap. Not toxic at all but in our society showing it may lead to putting up with assholes.
In other countries I've walked holding hands and even been kissed by both men and women where there was affection without sexual connotations, or perhaps suppressed if there were those feelings. I find it sad that in America and perhaps some other places too, we are not allowed that.
Down to your last paragraph, we (in our society) or I, don't openly celebrate love in its many forms because of the restrictive definitions we place on the word and what it really means. And sadly, even fear of it. I wish we could all openly celebrate it.