I could straighten that top tube on one headlight. I've straightened sailboat masts bent worse than that, same for a small sailboat dolly axle that hit a chunk of truck tread on the highway, was bent about a foot, to within 1/16" straightness, I was going to go closer but the guy who owned the trailer said that was close enough. Key is no dent and no kinks, just a gentle bend like your frame. I use a hydraulic press, a 4x4 at minimum on the bottom, at least the length of the bend, then 2x4s crosswise under the head tube and seat tube junctions, then put the top tube there convex side up, then a short 4x4 on top of the top tube, which the hydraulic ram pushes on. Take things slow. Bring the ram into contact, one pump on handle, release, all springs back. Then repeat, contact, 2 pumps, release, check if all springs back. Then repeat, contact, 3 pumps, release, check. Keep increasing number of pumps after contact until it doesn't spring back all the way, that means it's starting to yield. So for example, if 3 pumps and all springs back, and 4 pumps a bit of yield, you're gonna move it one pump at a time; 4 pumps, release, contact, 4 pumps again, etc. Partial pumps as you get close. Take your time. Or get a quote from a framebuilder or specialist in frame straightening.