April 30 of Golden Week 2022

I know it's really really early to be thinking about 2022 but I just cancelled my trip to see the snow wall for 2021.
Saturday April 30 is the beginning of Golden Week in 2022 followed by a working day on Monday May 2.
Itinerary:
April 23 Tokyo
April 24 Tokyo
April 25 Snow Wall
April 26-29 Osaka
April 30 KIX-TPE
Will April 30 be okay for departures from KIX or will it be very busy with the locals beginning their
Golden Week vacations?

April 30 would indeed be the busiest day for international departures out of Japan during GW 2022 if next year's GW would be a "normal" GW. I suspect, though, that international travel out of Japan will not be at the "normal" levels in 2022 yet.

Is this taking into consideration it's a split Golden Week without all consecutive days?

Frankly I donft see the problem departing on the busiest day, EXCEPT ticket prices. When I lived in Japan I had GW off, so I traveled then and I remember taking several times flights on the gbusiesth day. And itfs not a problem. I have much worse experience at some EU airports on gbusiest g days than ever in Japan.

The airports have capacity for the planes and passengers they serve. If you have a seat on a plane, it would be a pretty dull/typical airport experience if they were running at 100% capacity - the usual queues and waiting around. It is not like travelling by train without a seat and standing for your flight somewhere.
2022 isn't likely to be back to 100% normal.
Crowds during GW are often over-hyped - it is not like it is the busiest travel period of the year.