The claim is both misleading, and wrong from an objective point of view.
First, it is misleading because the numbers it refers to are the country's mean download speeds. In the objected countries, such as e.g. France (or even moreso Canada), a large number of people lives in rural, sometimes quite remote areas where, indeed, internet speeds are not always top-notch. Same problem here in Germany, if you live on a mountain top in the Hunsrück, well that's bad luck for gigabit internet access. But much unlike in Madagascar, you do get internet, only just it'll be none better than ADSL2+.
So, obviously, the mean ( = average) will reflect that negatively. Using the median would be a much more accurate and honest measure to begin with.
On the other hand, in Madagascar, if you have internet at all, you a) belong to a small elite and b) live in a large city where there exists a modern infrastructure. So yes, obviously, the famous last mile which is a dominating factor is much "better" for those who actually have internet. But all in all, the claim as such is deceptive, to the point of almost being a lie. Because "no internet" translates to 0Mbit/s.
Second, while a couple of better and more reliable links are planned for during/after 2019-2020, to date Madagascar as such is connected to the internet via exactly two cables, one being LION, the other being an odd route that finally ends in Mombassa in one direction where it has connection to SEACOM, TEAMS, and EASSy (plus some that are planned for 2020+) that finally end in FALCON, and has a connection to SAFE somewhere down south in Cape Town. Long lines that eventually end somewhere, and that hopefully conect to a high-bandwidth network, if nobody has pulled the cable.
There is thus the very unreliable route around the entire West African coast to connect to the Western World, and the route via the Arab world to connect with Asia, which is equally long and unreliable. Bandwidth is comparatively poor, but since there are so few users, currently nobody notices.
In summary, internet connection in Madagascar is poor.
I don't have the possibility of accurately measuring that now, but I wouldn't be surprised if you had "typical" everyday RTTs of 200-300ms to most "mainstream" services and locations. If I try to open e.g. the website of l'Express de Madagascar (a large newspaper) from my "mainstream European" location, the connection times out 50% of the time (
ping tells me 190ms, but what's
ping worth if you don't get a connection). The other 50% it looks something like:
9 seconds for connection establishment, 4-5 seconds to transmit a 12kB image file, that's undisputably not an awesome internet connection. That's figures you had in the early 1990s with a 14.4 modem...
Note that "internet" is not the guy living next door. Internet are those guys (and servers) living 1,200 or 5,000 kilometers away.
France, on the other hand, is directly connected to every significant network within Europe with reliable, high-bandwidth, low-latency lines, and with around 20 more or less line-of-sight undersea cables to US east coast. And, some, uh... well, not so great lines going far east (think FALCON), but the uplinks to these are still two or three orders or magnitude better than the African connection coming from the south, both in bandwidth/latency and reliability. Same for UK. Same for Canada, obviously, which has a very short and direct route to USA.
For European countries like France or UK (and Canada likewise), the speed of light is the biggest challenge (since it affects latency and is somewhat tough to improve on with our current understanding of physics). For Madagascar, getting a connection to something outside Madagascar at all is the challenge.