Assuming this is a genuine question, then yes I think it is a stealth tax.
If tax allowances don't keep pace with inflation, then the "real" value of our disposable income is eroded. To be totally accurate, if they are only raised onceper year, then that is a tax as well, because every month inflation is eating into our tax allowance, and an annual increase equivalent to the inflation rate is only a "catch up" - in arrears! In addition, our wages also need to rise with inflation, but that is not always a tax issue.
And for NJOK's benefit, the problem with tax is that it assumes that the government can do a better job of spending your money than you can. And this one definitely cannot. Throwing ever increasing sums of money at public services is a bit like pouring money down the drain. Our tax burden is higher than it has ever been, and with no discernible benefit.