This generational. I’ve seen a number of names I thought of as grandma names come back into fashion. People who are young enough not to have experienced grandmas with those names pick them. Gertrude is a grandma name to me, BTW, not a great-grandma name. I actually had a grandma named Gertrude. Welcome to old. (Edit: my brain glitched from Mildred to Gertrude there. Looking forward to Alzheimers.)