Thanks for the added info.
Here seems to be some good information concerning eMMC.
https://www.howtogeek.com/196541/emmc-v ... -is-equal/The memory is economical, which brings the chromebook cost lower, and it saves lots on power, but the trade-off is write-speed.
I see similar behaviour with an acer minibook, which also has this sort of eMMC memory. It's a bit of an expected tradeoff.
You may note the shutdown may be proportional to the number of programs, applications, and browser windows you have open when you decide to shutdown. If you prefer to restore on login, it means lots of info needs to be written down on shutdown so that it is available on login later.
The chromebook designers optimized this process for this type of hardware.
Mageia is structured for a more traditional computer setup expecting a faster harddrive.
FYI: Due to the eMMC, you may benefit in having your temp redirected to a RAMdisk. I assume the chromebook already has lots of RAM, however, more traditional distros like Mageia and others will default to the harddrive, or SSD unless you cutomize this.
I don't know the details for your HDD machine, so, cannot comment beyond HDDs are mechanical, and you're probably already familiar with expected speeds vs SSDs. You will likely benefit from choosing ext2 to avoid having the HDD head sweeping back-n-forth between data files and the journal.