Not only a drag, or not even a drag.
It's been a long while since I read The Innovator's Dilemma, but the ground-breaking thesis in that book as I remember is that established companies are disrupted because it's 100% rational for them to continuing pursuing and maximizing profit in their established market, even while obsolescence is knocking on their door.
The dilemma is that they have to choose between maximizing profits in their current market and returning unused capital to stockholders, or burning money on speculative investments in a bid to remain relevant in the future.
Were labor and capital markets frictionless, it wouldn't even be a dilemma. The answer would be obvious--choose the former. Any investments you divert from maximizing your current advantage is always a net loss. Excess capital is best given back to shareholders because "the market" will do better at choosing the next disruptive technology than any single person or business would be. That you're doomed to obsolescence and will eventually have to wrap up the business doesn't matter; what matters is maximizing profits.
But because labor and capital markets aren't frictionless, it's not optimal to let an existing business entity disappear. Think fixed costs like HR; or brain trusts. Finding the balance between maximizing your current market position and speculating on disruptive technologies is therefore arguably something worth pursuing.
But as labor and capital markets become more free and liquid, there's less of a dilemma.
Anyhow, long story short, companies aren't disrupted because they're dinosaurs and antiquated. They're slow to respond because it's often perfectly rational (i.e. more profitable) for them to ignore new technologies and to continue pressing their advantage until the very end. And that incentive aligns well with maximizing global profits and capital investments. The intuitive sense that companies are doing something wrong by not preparing for disruption is irrational as a general matter. You prepare for disruption by making as much money as you can and jumping ship at the very last moment; doing anything else is leaving money on the table.