I must express myself quite poorly. It is not a point about technical knowledge, in fact if you were to know more about the topic than I do, I would expect you to even more be upheld to higher standards and thus not promote a bad solution, even more so assume it's the only one. I can't imagine that even a PhD student who is supposedly at the frontier of knowledge in their very narrow field would assume no alternative is possible, or will ever be. This even more the case without having both a complete understand of the landscape but also about OP's actual needs, which is probably hard to express clearly and thus leading to a lot of assumption. Here maybe a simple loud alarm from a BT speaker going out of range might be enough.

My whole point is that abandoning hope, and leading others to do so, is worst than actively finding for a barely OK compromise.

Anyway I don't want to invest more energy on this discussion unfortunately so simply wishing you the best, thanks for the clarifications.