The Tarrasque is a flawed creature in all editions. In case of 1e/2e, it’s not immune to being stunned or being paralyzed (e.g. Hold Person), giving the party a good chance to exploit its vulnerable period. Later editions have other flaws, most of which can be fixed by giving the Tarrasque a ranged attack (similar to Godzilla, etc.)
The flaws in 3.5e actually involve power scale. There’s combinations of abilities that are incredibly powerful, resulting in characters that are pre-planned rather than organically grown - and also meant that some classes were inherently better than others. At the same time, there were feat taxes that were essential for almost any character, which would be cutting into abilities that would be normal.
However, I’d be comparing 3.5e to Basic D&D. In this case, I’d most likely prefer 3.5e, simply because it’s more flexible compared to the rigid use of Basic’s weapons, but I instead skipped past that and went to both 4e and/or Pathfinder.
I recall donationware being claimed to only provide a trickle amount - usually due to people being greedy and wanting to keep as much money as possible. Perhaps that was just that one person, but it’s still unreliable income source for the Dos shareware era.
Asking for donations doesn’t even solve the symptom of important software needing a team to scrounge funding. No publicly-important infrastructure should require begging.