Why do you think that they were lucky to get the draw? You admitted that he should have been called onside, and he dove? By that logic, Liverpool are unlucky to get a draw and Kane missing the first pen was sweet justice.
The second pen, while soft as hell, is a pen. Liverpool supporters are furious because of the lack of consistency in the officiating. The refs were letting them play during the game when players from both sides could have been taken off by red cards. (which is also something people aren't talking about because of the pen decisions) and then start calling things super tight and the end of the game. Which is usually backwards from how games are usually called. THAT is the problem.
The same officiating problem happened in the Palace, Newcastle game. A pen was called (rightfully) for tugging on shirts in the box, and then the same thing happens time after time after that pen call with no pen awarded. VAR is coming sooner rather than later.
With all of that said, this was another classic game though. Liverpool play the most exciting brand of football in the world.