Islam has not changed at all, I would say.
This is because God revealed the final message to Mankind with the promise that it would be preserved for the rest of time - until the Day of Judgment.
Muslims have changed, in may ways, with regards to their practice of Islam; but the Qur'an is the very same Qur'an that was recited by Muhammad. The evidence of that is, simply, that there were never any two different Qur'ans in the world. God's promise to protect Islam come true.
Further, the sayings and practices - the life - of Muhammad have all been documented quite clearly. Again, God promised to protect this final message and He has done so.
Muslims have been strict, or lax, from time to time. they have come under more literal interpretations of things and they have come under the influence of mysticism, as well. All these variations have occurred throughout time in different places and different times. So, there may be some Muslims who are strict in one part of the world and, at the very same time, liberal in other parts of the world.
Islam did not really change, the only way or reason it changed was the way the government changed it.
It has changed by being a shrine to and icon for Islam and Muslims around the world and millions of Muslims around the world to pray Allah
how the anemometer changed over time
The laws of physics have not changed over time. Our understanding of them has changed over time.
how has coal mining changed over time
People changed over time by growing up.
no they have changed over time. no they have changed over time.
how has neils bohr model changed over time
well it has changed over time bye people dancing it different styles.
how the seismograph change over time
how has deleware changed from 1776
his skills changed