Login page logo border-radius

In version 2.0 it seems that the login logo now has the following styles which cutoff all my login logo corners. It means I need to add a CSS fix to all my sites.

Can I ask if this addition was a necessary compatibility requirement or an aesthetic decision and if it will stay so I can plan the best method of altering all my websites.

.login h1 a {
    background-color: #FFF;
    border-radius: 50%;
}

Thanks.