My wife was an older student (28), who left college the first time when her mom died. She graduated in Math. Ed. with some absurdly high grade average. I have also taught physics classes in schools catering to older students, and in schools catering to the “typical” students.
Most of the positives listed for older students are absolutely correct. If maturity didn’t have its benefits, we wouldn’t mature. However, youth also has its advantages, and I disagree with what some of the others have said here. Maybe most young students take physics only because they have to, but they were all serious about it. Younger students can almost always drop everything for an important assignment or test, whereas if your boss says you’re working late, you’re working late. Be sure your profs know your situation.
The biggest problem I have seen with older students is stamina. Not the stamina to stay up all night, if need be. But either the stamina to be a full time student and work full time, or to be a part time student working full time who takes forever to graduate. Decide which kind of stamina you have. Are you the type who can put in 100 hours a week (job + commutes + school) for a few years, or the kind that can put in 65 for six?
E.g., you have kids. Kids not only demand time, but you want to spend time with them. Don’t take so many classes or spend so many years in school that you are a stranger to them when they hit high school. They won’t miss the extra money when they’re four, they’ll miss you. Look into on line coursework that can transfer.
My final piece of advice, applicable to all students, is to pay some attention, but not much, to the job market. Do what you love. One advantage of being an older student is knowing what that is. I know engineers and accountants supposedly get jobs more easily, and liberal arts types supposedly get promoted faster, yada yada. (Physics, by the way, is a liberal art and not a subfield of engineering. We can calculate like engineers, but intrinsically are closer to artists, which drives my engineer brother up the wall. Best or worst of both worlds???) You can’t predict the future. You don’t even know that you will end up doing. But you can know that you enjoy your current coursework, and that you have no chance of doing what you love, if you don’t have the education for it.
Your specific degree won’t matter that much to some employers. Competency in at least one field, the paperwork to prove you have good work habits, and fitting in are what most are looking for. (Not that philosophers get hired to program computers. Very often. But, then, if debating theology is your passion, programming probably would bore you into an early grave.)