What is the limit of sRgb then?
In what context? (There weren't any quotes there, so I'm not sure where this conversation continues from.)
Generally speaking, sRGB is a color space, which doesn't so much as change the number of representable colors...rather it changes the saturation and luminosity extents and white & black point of colors when modeled within that color space. You'll always have 24bits (8-bit RGB) or 48bits (16-bit RGB) of integer precision for each pixel, however with say AdobeRGB or ProPhotoRGB, the appearance of those colors when rendered may differ in comparison to sRGB, despite, technically, being "the same" color. In larger color spaces, a fully saturated "red" may appear more red and more saturated than in sRGB (and whether you have the ability to actually observe that would depend on whether your viewing device supports a gamut larger than sRGB itself!
Image Color Management (ICM) converts color information from one color space to another in L*a*b* (Lab) space, and colors are usually represented as high precision floating point numbers when doing so...so the number of mathematically representable colors is essentially "infinite". When converting back out of Lab to RGB, you may lose precision, and depending on the distribution of specific floating point color values in Lab, discrete color values in RGB may coalesce or end up clipped (sometimes depends on rendering intent, such as Absolute, Relative, or Perceptual.) Hence the reason why its useful to keep photos in the widest gamut (color space) possible until you actually have a reason to convert to sRGB (a smaller gamut.)