An Opinionated Decision Matrix for Which TTRPG System to Use
If your primary concern is getting people together at a table to play at all, pick D&D 5E. Everyone knows how to play it, it can be molded to meet the needs of any table, and there are countless off the shelf supplements already available to help a current or aspiring Dungeon Master.
The reality for many people is that it doesn’t matter which TTRPG system they use, because the struggle is going to be getting four or more adults together in a room for two or more hours in the first place. Under those conditions, the path of least resistance is the correct path, and that is almost always going to mean D&D 5E. There is nothing wrong with making this choice. It’s more important that you have fun with your friends engaging with a hobby you love than just about any other consideration.
If, on the other hand, your primary concern is literally anything else, then there is always going to be a better system to choose than D&D 5E. The reality is that it doesn’t matter how you choose to define “better” in this case, there’s going to be something that rises to the bar. The so-called “world’s most popular tabletop RPG” got there in the same way that Kleenex became the most well-known facial tissue. It is the lowest common denominator. Ubiquitous. Acceptable, though not aspirational. D&D is “good enough” most of the time. But if you have the time and the inclination, you can do better.
Someone out there has lovingly crafted a TTRPG system perfectly tailored to tell the kind of story you want to tell, and they want nothing more than for you to experience it and find joy. The only limit is the amount of time you can spend trying to find it and whether you can convince your friends to play it.