I looked into this and it appears this was an intentional UX decision we made. I believe the idea is to prevent too much undesired map movement. We do move the map if you search for a different place, but not when you modify or remove other filters.
Consider a case where you’ve moved and zoomed the map to an area you want to explore, and you modify the search filters slightly to see how that affects observation in the map viewport. If we were to zoom the map way out any time you changed or removed a filter, that might not be desirable, though that depends on personal preference and your use case.
Either way, this is an old and seemingly intentional UX choice unrelated to the bug report here. I’d suggest opening a separate request for modifying the map movement behavior on search changes, as this is unrelated to the reported bug of missing observation tiles and the map not focusing on observations on the initial page load.