I've honestly never had much trouble removing a square taper crankset with a decent crank puller. Some are a little fussier than others, but I've never had to put a whole lotta oomph into getting one off. Nor would I, knowing the threads in the crank arm are soft aluminum and not hard to strip.

When pulling a crank arm, remove the bolt and make sure there's no washer in the hole. We can see from the pic there's no washer in this case, but sometimes there is one. It'll keep the crank puller from pushing on the spindle and is a surefire way to strip something if you keep applying force. Also, make sure the outer part of the tool is fully seated before threading in the plunger. Use a wrench to get it a bit more snug than finger tight. If the outer body isn't threaded all the way in and seated firmly, that's another way you can strip your crank arm's threads.

If you've given it a fair (but not excessive) amount of torque and it won't budge, stop before something strips. Use some penetrating oil. Give it time to sit and do its thing, then try the wrench again. If it still won't budge, put the bolt or nut on, but only halfway. Leave a few mm of play between the nut and the crank arm. Then take the bike for a short ride down the block. Check the crank arm often to see if/when it comes loose. The instant it does, stop pedaling the bike because riding on a loose crank arm can deform the square cutout and ruin the crank arm.