The MSDS of CR2032 includes the compositionhttps://resources-boschsecurity-cdn.azureedge.net/public/documents/MSDS_battery_CR2032_Special_enUS_79832247051.pdf
Yes, some compounds are oxidizers. MnO2
is a strong oxidizer, LiClO4
an extreme one.
Lithium will make corrosive compounds if it encounters the atmosphere.
Will a leak occur? If a cell is pierced or crushed or corroded by some external action, yes. By discharge, my bet is: good quality cells won't leak, but poorly designed or manufactured ones will.
Removing the CR2032 has drawbacks in some circuits. I have known motherboards that don't start without a CR2032, or demand a Bios tuning at every start, possibly only after a hardware Cmos reset. Others start with degraded performance and with wrong clock time. More recent motherboards tend to behave better for that.
Corrosion can and will also occur if the electronic circuit leaks current, typically if it's damp. Then, all conductors are susceptible to corrode electrochemically. This does not relate with the battery type, except for its voltage and maximum current.