Find the online or paper catalog for your local city or county parks and recreation department -- whatever agency or organization does classes and teams etc. in your area. Sit down with him. Tell him he did fine completing two seasons of soccer and you know he doesn't want to play that (maybe he's burned out on it, mom, and not that into it as a sport, so don't force him to do soccer specifically). Then say, you and I together will pick an activity for this spring. You get a vote here, son. Play up the idea that he has some control and say in this. Then DO it.
If he has actually said out loud that he thinks he'll have more time for video games if he doesn't have another organized activity -- I hope you shut that down immediately. If he says it to you now, just say, "Sorry, pal, but you're going to be spending less time, not more, on video games." And make that happen, mom.
Also, remember -- he does NOT have to have a team sport. He might like to try something new and really different -- fencing and archery are great and really make a kid learn to focus. He might love a kids' drama class or an art class. Prompt him to think outside the area of a team sport; he's done that and got through it OK but isn't in love with it, so encourage another area altogether.
Also, have you ever looked at Boy Scouts for him? A good troop will do lots of different kinds of activities throughout the year so there are changing things to keep a kid interested. (Check out a troop by talking to parents you know -- some troops do focus very heavily on one area, like my godson's old troop that pretty much camped every single month and that was all, but every troop is different!). Your son can manage both scouting (or a church youth group, or a school club, etc.) at the same time he has school and an outside activity too.
Don't let an eight-year-old drive the decision on what he does. Parents who do that end up posting on here about how their kids sit around all the time playing video games and "running around the neighborhood" (when that really translates to being at other kids' houses....playing video games). It is definitely not overscheduling him to have him in an activity AND have him participate in things at school such as an after-school club (they don't meet often or for long, at his age) or one-time charity drive etc. He's eight, and is naturally going to say he doesn't want to do anything. If he won't pick -- pick for him, but don't just fall back on soccer because he's done it in the past or because "all the other boys do it." If he's over it, he'll be bored there and act out; he may not truly hate it but he also should be in some activity that will at least be new enough to get his attention for a time.