They do, but not in the same way BFR does.
Every time muscles contract, the muscle fibres shorten end to end but bulge out side-to-side, which is why flexing your bicep makes it “pop”. When these muscles fibres expand, they compress the capillaries and arterioles around them. This reduces blood flow (both oxygenated and deoxygenated) to contracting muscle fibres for the period of their contraction, and limits gas exchange. Because of this, contracting muscles do not recieve oxygen and cannot remove CO2 until they stop contracting.
BFR training, in contrast, provides enough compression to stem venous blood flow out of the cuffed limb, but does not affect arterial blood flow. This is because there are major veins close to the skin, but major arteries are deep, and because veins have a somewhat “flimsier” structure. Because of this, when BFR is applied to a limb, the venous blood (which carries CO2 and metabolites back to the heart) is trapped in the limb, but fresh blood can still enter.