Yes. So why fit a 100Mb/s port on a 200Mb/s homeplug?
Many homeplugs incorrectly quote the full duplex speed, ie can send 100Mb/s and receive 100Mb/s = 200Mb/s, but it's really a 100Mb/s connection.
Also bear in mind that it is quoting it's maximum possible speed, you'll not likely get that in most cases.