Correct. It does support what you said. With that being said, Catholics are obligated to attend Sunday Mass. That to me means one should be in attendance for the entire Mass if it is at all possible. Sometimes it isn’t, I suppose.
I don’t think I’ve been late to Sunday Mass in my life, though I do recall arriving just after Father arrived on the altar for a daily Mass once, so I really don’t understand why this is an issue for a lot of folks that are habitually late. I do know some folks have jobs that require them to be somewhere else on an emergency basis and sometimes folks have something come up on an emergency basis, and some folks have schedules that prevent them from arriving earlier on a general basis, but for most folks, I think they generally should be able to arrive at Mass before it starts.
When I was a kid, a family of ten at our parish always arrived a few minutes after Mass started. All ten of them went up to the front pew of Church week after week after week, just a few minutes after Mass began. I would think they could have adjusted their schedule just a few minutes to avoid doing that. But, it was their habit. I think sometimes that is the reason some people arrive late to Mass on Sunday. It is just what they do.