Windows Live Mail?
"in 2017 found Windows Live Mail had one per cent market share"
What has this to do with the Mail app in W10?
WLM has been abandonware for years now and difficult to get hold of. I haven't spent much time on trying it out on W10 (upgrade from W8.1) but it didn't seem happy.
Still running it under W7 and W8.1 because it reminds me of Outlook Express and I like the user interface.
Thunderbird is my emailer of choice on socially supported W10 systems for friends.