You can’t do anything because these excuses are window dressing and not the core of the issue. The core of the issue is that 99% of people are incredibly unwilling to change their habits or spend five minutes to wrap their heads around how things work. If the question of which server to join is too much, this kind of space isn’t for you.
No, having a full time job or a family is not an excuse to not learn how computers or the internet or networks in general work. You’ve had a lifetime to learn and are willfully ignorant. If you just give up and run away the moment you have to apply two braincells to understand a new concept, your cognition is fucked.
Im personally fine with basic competence and tech literacy to be a natural gate keeping the unwashed morons out. Lemmy is growing at a fine pace without catering to the lowest common denominators.
Three is better than none. as long as the community exist and has some kind of activity even one post a month with three comments, you are doing your part to create a viable home for those who share your niche interest. In three months you might get up to 6 people, in 9 months 10, one year later 15. Its difficult going from passive consumer to one of the few active posters but you truly are adding value to the space just by trying.
Lemmy users like to present lemmy vs reddit usage as all or nothing, its not. Realistically you still use reddit for the niche communities that arent getting much interaction here. I do for locallama and dynavap. But ideally you cross post to the lemmy communities to add content here too so that those like you have a better chance to find a home.