No the employer is entitled to the value of the product or service. They are not entitled to the value created by their workers.
Your Second argument is false as well because they don’t get to pass on manufacturing and designing cost to the workers! That cost should be passed onto the customer. Your argument is lie that workers should have no work without the benevolence of their employers. If their work is so meaningless that the owners are entitled to the workers pie then way do the owners need them at all? It’s the reason why corporations always threaten to replace workers with machines or outsourcing but never actually do it. It’s because the true value in a for profit company is how much value you can steal from the lowly workers. In the machine threat, hiring a electrical, robotic, and software engineers cost more than 1000 minimum wage workers. But they can’t steal those engineers value because they are well educated and know their value. It’s what the 100% of the GOP and 50% DNC hate education. Education prevents exploitation… As for outsourcing all workers are catching onto the theft and are fighting back as well. Add in shipping costs, bad pr, taxes, and time, no way outsourcing will grow like it did in the 80s/90s/2000s.