Not completely. Software can imitate the miniature look, but it usually has limits compared with optical blur from a lens.

The biggest issue is depth: many tilt-shift-style filters apply blur based on a simple band or gradient across the frame, not the true distance of each subject. That can look fake when different parts of the same object should share similar focus but don’t. A more convincing result would require a detailed depth map of the scene.

A real lens produces blur based on actual scene geometry, so the rendering is usually more natural. That said, even a tilt-shift lens doesn’t perfectly match the look of photographing a real miniature.

Also, many software miniature effects add heavy saturation or contrast, which is stylistic rather than inherent to tilt/shift optics.

One important note: a tilt-shift lens is not specifically a “miniature effect lens.” Tilt is designed to control the plane of focus, often to keep subjects sharp in ways a normal lens cannot, while the miniature look is a side effect of using that control creatively.

So: software can get close for many images, but it cannot always reproduce the depth-aware, optically natural rendering of a real lens.