Need feedback about my strategy to invest in GOVZ/ZROZ?

I have been market for few years and know quite many things but I don't consider myself expert.

I have some allocation in stocks and some in bonds.

I invest those bond allocation in GOVZ. Here is my thinking:

1. Interest rates go down – The ETF will make major gains and I can exit it in the future

2. Interest rate stay the same – ETF will still make slow up moves because of the coupon it receive from underlying

3. Interest rate increases – Let's say they increase from 3% to 5%. The ETF will go down. It's a scenario where I lose but interest rates are most likely to down in 5 year period. So chance of this are very low.

In worse case, I can exit it and buy 25-30 year close date treasury directly from my broker. Eventually it will expire after 25-30 years giving me an interest of 3%

That's my thinking process. I am not going all into GOVZ. But considering the low possibility of interest rate going up in 5 years, it's a very good buy for now.

Feedback?