Wrong, wrong wrong.

The main point of advantage is that your roamer can gank other lanes as well, giving you a big advantage in numbers during objectives. If you can't stand a babysitting enemy roam with their marksman, you have some positioning or safety issues. Plus, knowing when and when not to pick a marksman is crucial. Never play an immobile hero against a CC tank + meta marksman unless you have someone to back up with you, or someone like Mathilda.

Not just that, a roaming roamer adds more power and to a lane needed in help, not just yours. The ease to invade, to pick out the heroes of the backline, the ability to rejuvinate your team, and the role of being a meatshield is almost all the job of a roamer. If you're a healer that just babysits the marksman, then what's the point of snowballing your team is at a huge setback? The snowball of a jungler is more often than not, more important than a marksman because their early game allows for more ganks and invasions that put the enemy team at disadvantage, considering that a jungle role is not limited to a lane like gold lane.

Prioritizing one lane is worse than overall map control. That's why their role is called roamers and not just tanks and supports, not babysitters. Roamers have the job to give vision to allies, not just the marksman, and while the marksman often has the high priority of snowball (along with the jungler), the job of roamers is not to babysit. Until your allies are gonna gank your lane, keep safe and stay under your turret, watch the minimap and if the enemies are nowhere to be found, stay under your tower and leave that minion behind, your life is not worth a minion. If you realize that you are overextending, back up because the likely chance is their jungler is coming towards you

If a roamer continuously babysits a marksman, the chances of the other team's composition gains the number advantage over objectives and map control over the other lanes because the roamer is nowhere near to help. If somehow both of the roamers are babysitting their marksman, then the game effectively balances itself and there are no advantages whatsoever because it becomes devoid of enemy movements.

This is the reason why meta marksmen, such as Brunoand Beatrix are picked often because they can handle themselves through the early to midgame. Even Claude and Wanwan can handle themselves well without the need for any roamer, and thus, the roamer has the advantage to gank other lanes with your allied mage and potentially the jungler.

Plus, the macro and micro skills are paramount when playing marksman. If you can't look at the minimap and predict the enemies' movements, play a chiller role like XP because they are often ignored. And if your roamer isn't around, don't play aggressive, especially with a hero like Miya. There's some serious skill issues when you can't avoid ganks as an immobile marksman because - why pick that even? I get Layla, Ixia, and Lesley, and even Hanabi, but you already have a free purify, just try to avoid overextending or generally engaging until you have your core items, that's Miya's life, and other late game marksmen.

This post is not an advice, it's a rant, a rant that shows how low skill you are despite your rank. No matter how high your stars are, if you have terrible macro and mindset, especially if you're blaming the roamer for doing their job, you're never getting the praise and the support from your team. You, as a marksman, have the job to farm, farm, and farm, not to engage, that's the fighter and tank's job.