I dont agree that Islam is one acceptable way of achieving paradise..
As long as you believe in one God and do good to others sincerely, you have just as good chance in achieving paradise.
This is of course about those who have little or incorrect Info on islam, or they’ve never come across it in the first place ( not so common anymore).
Then there are the ahle kitaab who do not associate with God.. and people who have no control or freedom in their life path ( poor/ illiterate/slave/prisoner etc.)
Each will be judged on their individual circumstances and and on their level of sincerity. But thats what it will all come down to in the end, even if you call yourself a muslim.