I'm of that age where I know him and Jean-Claude Van Damme from loads of 80's action movies.
After having spent over a decade in an Inosanto blend of arts (really Kali, Arnis, Wingchun, Kuntao/Silat, some JKD sets) I think the thing he did which was unusual was that he actually made Aikido look really practical. Any time I've seen it taught locally, especially when it's something like Daito Ryu (close cousin), it's just... good theatre maybe? Really arcane self defense situations seem a lot less likely in the modern world (or in less organized warlike societies such as Filipino Morro). Morihei Ueshiba and some of his direct students were probably amazing but in a lot of cases it's a thing of these guys actually being great natural fighters to begin with, and without building that foundation first it's really tough to guide yourself on how to use techniques in a way that make timing, reach, and effectiveness sense.
So I give him credit for making Aikido look boss in ways that I hadn't seen before. I still haven't seen the schools and lesson plans though that create the missing link from mental chi / ki exercises and stopping a palace guard from drawing his sword/dagger on one hand and doing what Seagal does which... almost looks like a forerunner of Russian Systema Spetsnaz where aggressive application of Aikido mixed with other things is a given.
For acting though - a lot of martial artists will be Michelle Rodriguez equivalents, ie. they get scripted not to act but play some variant of themselves along alternate narrative arcs and it's really unlikely you'll see a movie with them in it and not realize it was them unless they were half lens-blurred feeding pigeons in the background somewhere for a few moments.
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The loneliest part of life: it's not just that no one is on your cloud, few can even see your cloud.