Peace janab-e-ali
While what you say is an alarming shame I detect a tone of sarcasm in your post and must retort that your comparison is still not adequate. Tearing down “Islamic historical sites” you need to substantiate that claim. They were houses and homes of the salaf. They have new ones in Jannah they will not miss them here on Earth!
Please look at this graph:
You will see that population in the world has remained below 1 billion up until the latter few centuries of the previous millenium. Logic will tell us that due to technology constraints and lower population the amount of people visiting Makkah historically has been considerably less than in the past 50 years. Logically something needed to be done the facilitate things for hajjis, again I disagree with some aspects such as the high rise hotels with western influenced business establishments, but you need to concede that for some things there is no other choice. This could be the reason why for such a long time the “historical sites” have been kept for so long until recently, it may have nothing whatsoever to do with your allegation against the religious disposition of the Saudi government.