Thanks, bert, although your CAPS LOCK key appears to be stuck.
You are correct. Interest earned in a Tax-Free Savings Account does not affect the Guaranteed Income Supplement or Old Age Security clawback rules. This is why a TFSA is ideal for retired folks who, for years, have kept large balances in their chequing accounts that pay like 0.05% interest because they don't to earn much interest that affects the tax they pay or the government income they receive.
Cheers,
Doug