My Dad worked for Swift & Co. for 45 years. Nonetheless, when I quit my first job, he said to me, approvingly, "They're not loyal to you, so why should you be loyal to them?" There are companies loyal to their employees. They tend to be small and family-owned, though, and when the family retires or loses control, the new owners tend to be markedly less loyal.
What does it mean to be "loyal to" a company or employee, though? Maybe I'm just overly cold and "literal", but an employment agreement is just that: an agreement to exchange value for value. In general, I loathe the idea of an agreement that I can't renegotiate. Do I owe my employer something? Yes, to the extent that it is agreed upon contractually. Does my employer owe me something? Same deal. I just don't understa…
In exchange, I have more reason to stay and provide continuity, preserve domain knowledge, etc.
It's ok to have a cold or literal view of an employment agreement. In my opinion that's valid, and looking at your agreement through that lens gives you a lot of information about the intended term or duration of the agreement. Sadly, it's increasingly common for that duration to be "until the next re-org or downturn".