Not as good as the local sim (in Asia not by a long mile if I recall correctly), but it's way more convenient. Then again, here we can get some daily limited (500MB-1GB, depending the country) data roaming packages for the equivalent of 1-2€ daily. If it's quite a few days I'd go local sim, it's a bit of a hassle the first day, but their data packages are silly cheap. I guess in Europe/US/Canada I'd consider seriously some Airalo or equivalent.
With Airalo? Not really. If you manage to get the eSIM from the local provider, then sure, you can get the same rates, and before you even pack for the trip. But not all local providers are so readily to offer you an eSIM. And Airalo offers convenience at a not terrible rates, but definitely the best rates are local providers, physical or eSIM.
It's also the ease of it. I travelled to Indonesia a while back thinking I could pick up a SIM card once there. I didn't realise you have to register the phone itself for tax reasons (?) to white list the IMEI of the phone before buying a SIM card. It was loads easier just to buy a roaming eSIM after I arrived. In hind sight I probably could have got a better package had I shopped before hand but it got me out of a tricky situation.
Same issues in Turkye. You have to track down a shop and they'll fleece you because they flat out refuse to sell you the cheap options under various pretexts. If you use the SIM for 6 months you have to register your IMEI, and if you don't they expire and you have to do it all over again. So yeah, having an eSIM is a big improvement.