I work at a company that has a reputation for squeezing the most out of its employees, although the group I'm in doesn't share the same "burnout" type culture that the rest of the company shares (it helps that we're internally facing and not subjected to customer emergencies at odd hours of the night). I don't feel overworked, and generally I like my job, but what I'm noticing is a disturbing trend in that, to get ahead (i.e., promoted) in this company you basically need to do something amazing and groundbreaking by building something outside of normal work hours.

There is a slight problem in that, we have a full load of "day to day" operational responsibilities (with more getting piled on each day), which leaves less and less time for doing innovative and groundbreaking work which we can surface for our end of the year review. Personally, I adhere quite closely to 40 hours a week, constrained mostly by my family (I have a wife and kids), as well as outside activities (I'm involved in a leadership position at a local non-profit as a volunteer). All of my co-workers are unmarried and without kids, so naturally the time they have available is greater.

Now, I don't resent this because I chose to get married and have kids and they didn't (we're all fairly close in age, so it's not like I'm a decade older). Our defacto team lead (who is an awesome guy btw) has dedicated a lot of time outside of work to learn additional skills, which I think is great. The issue that I see is that he spent his nights and weekends for several months building a project for a class he took, and then he was able to convince management to relinquish all of his existing day to day activities in order to turn this project into something viable for the business. He's been able to dedicate himself 100% on this project, while the rest of us are stuck taking care of the day to day operational tasks (most of which unfortunately seem to be pointless to the majority of stakeholders). We keep asking our boss to reduce the level of hand-holding that goes on to free up our time for more interesting and meaningful work, but even though he promises it will change in the future, I have my doubts.

I look at this, and wonder how I can even compete when I'm not able to play at this level (and yes, when it comes down to it, because this company does stack-ranking, this is a competition). My boss has more responsibilities now (managing a larger team), so he's not able to counsel me as often as he used to, and I feel like because there is no end in sight for the burden that day to day activities take on my job, I don't really have a chance to make my mark, so to speak.

Is my thinking incorrect, in that should I just either suck it up and work extra hard outside of my normal job to try and produce something extraordinary? I understand the idea of you get what you put in (and I have been in roles in the past where I did put in a ton of work and reaped the rewards for doing so), but I feel like there is a general imbalance here because my coworker was able to dedicate an extraordinary amount of time outside of work building a product that eventually came to replace all of his day to day operational work, hence allowing him to propel his career forward.

Since conversations with my boss haven’t really borne any fruit, my first instinct is to just leave. Any other suggestions here?

EDIT: One thing I should add to the original post is that I feel an immense amount of pressure to get promoted, because my boss has been gearing me up for it almost immediately after I joined, and brings it up every few months. The problem is I feel like I have not been able to accomplish anything meaningful in my time here thus far, hence my conundrum about feeling demotivated about this whole thing.

I work at a company that has a reputation for squeezing the most out of its employees, although the group I'm in doesn't share the same "burnout" culture that the rest of the company does. 

I generally like my job, but what I've noticed that in order to get ahead (i.e. promotions, raises) you basically need to spend your own personal time developing improvements and solutions for the company. Performing your day to day responsibilities (even if you do so very well) is not enough.

As a family man I don't have the option to dedicate my personal time toward this sort of thing. I'd like to work my 40 hours and spend the remaining time with my wife and children. My team-mates, however, are all able to dedicate themselves to these after-work work projects.

Recently one of them developed a solution which has now become his full-time, at work, project, while his former responsibilities have fallen to the rest of us. I am so swamped with routine responsibilities that I have no time to work on additional projects at work.

Up until this point my boss had been grooming me for future promotion, and I had been pressured to perform, and thus rise in the ranks. However, especially now that my plate is so full, I don't feel like I can compete with my team-mates.

Is it unreasonable to feel that this lack of life/work balance, and the pressure to innovate on your own time are good reasons to quit the company?

EDIT: One thing I should add to the original post is that I feel an immense amount of pressure to get promoted, because my boss has been gearing me up for it almost immediately after I joined, and brings it up every few months. The problem is I feel like I have not been able to accomplish anything meaningful in my time here thus far, hence my conundrum about feeling demotivated about this whole thing.