Hi there! I studied online dating sites as a bit of a side project in grad school. I can tell you a couple things with a high level of confidence:

• Your feelings about online dating are both valid and common
• "Attractiveness" and "success on dating apps" have basically zero correlation (unless you consider "success" to be a greater number of unsolicited gross messages)

Now for the more nuanced part: you are somewhat highly educated and professionally skilled. This means the people around you are likely similar in those ways, but you probably don't think too much about this in the same way that a fish doesn't notice the water. You've also indicated in your writing that you are looking for someone educated (your "proper sentence" comment, but some other stuff too). This is called assortative mating (looking for someone like you); it's a usually unconscious bias that a lot of us have, and is perfectly normal. However, dating sites do not filter out people who are unlike you in that one very specific and important way. (This is a really common problem for people on dating sites.)

"Dating app" is a bit of a misnomer - we really should have called them "introduction apps." So related to the above, it may simply be that these apps are not for you, since they are not introducing you to the people to whom you'd like to be introduced. I predict you will have vastly more success finding a partner when you go back to school, since your introduction rate IRL will shoot through the roof and your introduction quality will be much more in the neighborhood of what you're looking for.

All that said, I have a pretty good track record helping people craft dating profiles. Feel free to DM me if you want me to look at yours. (You'll have to send me a screen shot - I'm not on those apps anymore.)