Well this is your choice; it’s an activity bottleneck, not a roadblock imposed by the game. For those who are minded to run M+ anyway because it’s an activity they do for the sake of the activity, sparks simply don’t drop often enough to keep up with them and there doesn’t seem to be anything they can do about it.
I… don’t see this in my experience. My guild’s mythic team is currently working on their 4th boss. About half of them have done +20s other than SBG. The others are mostly in the 17-18 range.
Maybe it changes at the later bosses, but so far, my experience is that bosses 1-3 are easier than, say, a +20 Halls of Valor on tyrannical week.
If you really don’t have any days where you’d have 2-3 hours to play continuously then I sympathise.
But in general, most people can find that, even when they have families. And the actual raid night is usually more compatible with, for example, young children, because if you need to step away for moment that’s fine, just try to wait until the end of this particular pull. Most fights are over in 5-6 mins, it’s not often that people have emergencies so severe they have to be immediately handled.
Meanwhile in M+, you sit down and you commit to the timer. You don’t get up for the next 30-40 minutes unless you want to brick the key. I personally find this more demanding because there’s no breaks in concentration for that period, but to each their own.
Once you have it on farm, it becomes pretty solid reward for time. You’ll get a new piece of gear for about 50% of the team by clearing the first 3 bosses, which can be done inside an hour once you have it down. This is far better than M+ where after a point the only rewards are in your vault.
It’s completely valid to just not like raiding and not want to do it, but for all the non-organisers in the team, raiding is mostly about making sure you clear your schedule for a few hours on a particular day, and doing the basic prep of consumables and tactics guides at any time during the week.
Raid leaders will sweat it hard, but that’s why they’re generally the people with plenty of time. You don’t have to raid lead if that doesn’t work for you 